From a884e0e058a3ac474f296b2afbd330654690cfeb Mon Sep 17 00:00:00 2001
From: Isse <isidornie@gmail.com>
Date: Sat, 3 Jun 2023 22:14:18 +0000
Subject: [PATCH] Various rtsim related stuff

---
 CHANGELOG.md                              |   2 +
 assets/voxygen/i18n/en/npc.ftl            |   4 +
 client/src/lib.rs                         |   4 +-
 common/net/src/msg/server.rs              |   6 +-
 common/src/cmd.rs                         |   7 +
 common/src/comp/body.rs                   |  26 ++
 common/src/comp/inventory/item/modular.rs |   1 +
 common/src/mounting.rs                    |  22 +-
 common/src/resources.rs                   |   7 +
 common/state/src/state.rs                 |  11 +-
 rtsim/src/ai/mod.rs                       | 397 +++++++++++++++-------
 rtsim/src/ai/predicate.rs                 |  93 +++++
 rtsim/src/data/mod.rs                     |   2 +-
 rtsim/src/data/npc.rs                     |   2 +-
 rtsim/src/event.rs                        |  10 +-
 rtsim/src/lib.rs                          |   5 +-
 rtsim/src/rule/npc_ai.rs                  | 300 +++++++++-------
 rtsim/src/rule/simulate_npcs.rs           |  67 +++-
 server/src/client.rs                      |   2 +-
 server/src/cmd.rs                         |  77 ++++-
 server/src/events/interaction.rs          |  30 +-
 server/src/rtsim/mod.rs                   |  31 +-
 server/src/sys/entity_sync.rs             |   5 +-
 world/src/sim/mod.rs                      |   3 +-
 world/src/site2/plot/bridge.rs            |   2 +-
 25 files changed, 824 insertions(+), 292 deletions(-)
 create mode 100644 rtsim/src/ai/predicate.rs

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 47900be019..2d53a3d006 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -87,6 +87,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Underwater fall damage
 - The scale component now behaves properly
 - Multiple model support for dropped items (orichalcum armor)
+- Made rtsim monsters not go into too deep water, and certainly not outside the map.
+- Fixed bug where npcs would be dismounted from vehicles if loaded/unloaded in a certain order.
 
 ## [0.14.0] - 2023-01-07
 
diff --git a/assets/voxygen/i18n/en/npc.ftl b/assets/voxygen/i18n/en/npc.ftl
index c07d12b26b..d80f37e8a8 100644
--- a/assets/voxygen/i18n/en/npc.ftl
+++ b/assets/voxygen/i18n/en/npc.ftl
@@ -269,6 +269,10 @@ npc-speech-witness_death =
     .a0 = No!
     .a1 = This is terrible!
     .a2 = Oh my goodness!
+npc-speech-welcome-aboard =
+    .a0 = Welcome aboard!
+    .a1 = Can I see your ticket... just kidding it's free!
+    .a2 = Have a nice ride!
 npc-speech-dir_north = north
 npc-speech-dir_north_east = north-east
 npc-speech-dir_east = east
diff --git a/client/src/lib.rs b/client/src/lib.rs
index 1e073b9848..0e2dc2c0f4 100644
--- a/client/src/lib.rs
+++ b/client/src/lib.rs
@@ -2233,7 +2233,7 @@ impl Client {
                     return Err(Error::Other("Failed to find entity from uid.".into()));
                 }
             },
-            ServerGeneral::TimeOfDay(time_of_day, calendar, new_time) => {
+            ServerGeneral::TimeOfDay(time_of_day, calendar, new_time, time_scale) => {
                 self.target_time_of_day = Some(time_of_day);
                 *self.state.ecs_mut().write_resource() = calendar;
                 let mut time = self.state.ecs_mut().write_resource::<Time>();
@@ -2249,7 +2249,7 @@ impl Client {
                 } else {
                     0.99
                 };
-                self.dt_adjustment = dt_adjustment;
+                self.dt_adjustment = dt_adjustment * time_scale.0;
             },
             ServerGeneral::EntitySync(entity_sync_package) => {
                 self.state
diff --git a/common/net/src/msg/server.rs b/common/net/src/msg/server.rs
index ca2d87c9e2..d626017eaf 100644
--- a/common/net/src/msg/server.rs
+++ b/common/net/src/msg/server.rs
@@ -11,7 +11,7 @@ use common::{
     lod,
     outcome::Outcome,
     recipe::{ComponentRecipeBook, RecipeBook, RepairRecipeBook},
-    resources::{Time, TimeOfDay},
+    resources::{Time, TimeOfDay, TimeScale},
     shared_server_config::ServerConstants,
     terrain::{Block, TerrainChunk, TerrainChunkMeta, TerrainChunkSize},
     trade::{PendingTrade, SitePrices, TradeId, TradeResult},
@@ -195,7 +195,7 @@ pub enum ServerGeneral {
     ChatMsg(comp::ChatMsg),
     ChatMode(comp::ChatMode),
     SetPlayerEntity(Uid),
-    TimeOfDay(TimeOfDay, Calendar, Time),
+    TimeOfDay(TimeOfDay, Calendar, Time, TimeScale),
     EntitySync(sync::EntitySyncPackage),
     CompSync(sync::CompSyncPackage<EcsCompPacket>, u64),
     CreateEntity(sync::EntityPackage<EcsCompPacket>),
@@ -342,7 +342,7 @@ impl ServerMsg {
                         | ServerGeneral::ChatMsg(_)
                         | ServerGeneral::ChatMode(_)
                         | ServerGeneral::SetPlayerEntity(_)
-                        | ServerGeneral::TimeOfDay(_, _, _)
+                        | ServerGeneral::TimeOfDay(_, _, _, _)
                         | ServerGeneral::EntitySync(_)
                         | ServerGeneral::CompSync(_, _)
                         | ServerGeneral::CreateEntity(_)
diff --git a/common/src/cmd.rs b/common/src/cmd.rs
index 9e1523bdf6..d65800b8df 100644
--- a/common/src/cmd.rs
+++ b/common/src/cmd.rs
@@ -328,6 +328,7 @@ pub enum ServerChatCommand {
     Sudo,
     Tell,
     Time,
+    TimeScale,
     Tp,
     Unban,
     Version,
@@ -722,6 +723,11 @@ impl ServerChatCommand {
                 "Set the time of day",
                 Some(Admin),
             ),
+            ServerChatCommand::TimeScale => cmd(
+                vec![Float("time scale", 1.0, Optional)],
+                "Set scaling of delta time",
+                Some(Admin),
+            ),
             ServerChatCommand::Tp => cmd(
                 vec![
                     PlayerName(Optional),
@@ -894,6 +900,7 @@ impl ServerChatCommand {
             ServerChatCommand::Sudo => "sudo",
             ServerChatCommand::Tell => "tell",
             ServerChatCommand::Time => "time",
+            ServerChatCommand::TimeScale => "time_scale",
             ServerChatCommand::Tp => "tp",
             ServerChatCommand::RtsimTp => "rtsim_tp",
             ServerChatCommand::RtsimInfo => "rtsim_info",
diff --git a/common/src/comp/body.rs b/common/src/comp/body.rs
index 038641091b..087a709df4 100644
--- a/common/src/comp/body.rs
+++ b/common/src/comp/body.rs
@@ -103,6 +103,32 @@ pub struct AllBodies<BodyMeta, SpeciesMeta> {
     pub arthropod: BodyData<BodyMeta, arthropod::AllSpecies<SpeciesMeta>>,
 }
 
+impl<BodyMeta, SpeciesMeta> AllBodies<BodyMeta, SpeciesMeta> {
+    /// Get species meta associated with the body.
+    ///
+    /// Returns `None` if the body doesn't have any associated meta, i.e ships,
+    /// objects, itemdrops.
+    pub fn get_species_meta<'a>(&'a self, body: &Body) -> Option<&'a SpeciesMeta> {
+        Some(match body {
+            Body::Humanoid(b) => &self.humanoid.species[&b.species],
+            Body::QuadrupedSmall(b) => &self.quadruped_small.species[&b.species],
+            Body::QuadrupedMedium(b) => &self.quadruped_medium.species[&b.species],
+            Body::BirdMedium(b) => &self.bird_medium.species[&b.species],
+            Body::BirdLarge(b) => &self.bird_large.species[&b.species],
+            Body::FishMedium(b) => &self.fish_medium.species[&b.species],
+            Body::Dragon(b) => &self.dragon.species[&b.species],
+            Body::FishSmall(b) => &self.fish_small.species[&b.species],
+            Body::BipedLarge(b) => &self.biped_large.species[&b.species],
+            Body::BipedSmall(b) => &self.biped_small.species[&b.species],
+            Body::Golem(b) => &self.golem.species[&b.species],
+            Body::Theropod(b) => &self.theropod.species[&b.species],
+            Body::QuadrupedLow(b) => &self.quadruped_low.species[&b.species],
+            Body::Arthropod(b) => &self.arthropod.species[&b.species],
+            _ => return None,
+        })
+    }
+}
+
 /// Can only retrieve body metadata by direct index.
 impl<BodyMeta, SpeciesMeta> core::ops::Index<NpcKind> for AllBodies<BodyMeta, SpeciesMeta> {
     type Output = BodyMeta;
diff --git a/common/src/comp/inventory/item/modular.rs b/common/src/comp/inventory/item/modular.rs
index 872b84c213..fceea44e18 100644
--- a/common/src/comp/inventory/item/modular.rs
+++ b/common/src/comp/inventory/item/modular.rs
@@ -99,6 +99,7 @@ impl ModularBase {
         hand_restriction.unwrap_or(Hands::One)
     }
 
+    #[inline(never)]
     pub(super) fn kind(
         &self,
         components: &[Item],
diff --git a/common/src/mounting.rs b/common/src/mounting.rs
index 52d378f0f8..0cb1e812c5 100644
--- a/common/src/mounting.rs
+++ b/common/src/mounting.rs
@@ -173,18 +173,18 @@ impl Role for VolumeRider {
 }
 
 #[derive(Serialize, Deserialize, Clone, Copy, PartialEq, Eq, Debug, Hash)]
-pub enum Volume {
+pub enum Volume<E> {
     Terrain,
-    Entity(Uid),
+    Entity(E),
 }
 
 #[derive(Serialize, Deserialize, Clone, Copy, PartialEq, Eq, Debug, Hash)]
-pub struct VolumePos {
-    pub kind: Volume,
+pub struct VolumePos<E = Uid> {
+    pub kind: Volume<E>,
     pub pos: Vec3<i32>,
 }
 
-impl VolumePos {
+impl<E> VolumePos<E> {
     pub fn terrain(block_pos: Vec3<i32>) -> Self {
         Self {
             kind: Volume::Terrain,
@@ -192,12 +192,22 @@ impl VolumePos {
         }
     }
 
-    pub fn entity(block_pos: Vec3<i32>, uid: Uid) -> Self {
+    pub fn entity(block_pos: Vec3<i32>, uid: E) -> Self {
         Self {
             kind: Volume::Entity(uid),
             pos: block_pos,
         }
     }
+
+    pub fn try_map_entity<U>(self, f: impl FnOnce(E) -> Option<U>) -> Option<VolumePos<U>> {
+        Some(VolumePos {
+            pos: self.pos,
+            kind: match self.kind {
+                Volume::Terrain => Volume::Terrain,
+                Volume::Entity(e) => Volume::Entity(f(e)?),
+            },
+        })
+    }
 }
 
 impl VolumePos {
diff --git a/common/src/resources.rs b/common/src/resources.rs
index 4722c4e8b4..64daaeb7ab 100644
--- a/common/src/resources.rs
+++ b/common/src/resources.rs
@@ -13,6 +13,13 @@ pub struct TimeOfDay(pub f64);
 #[derive(Copy, Clone, Debug, Default, Serialize, Deserialize, PartialEq)]
 pub struct Time(pub f64);
 
+#[derive(Copy, Clone, Debug, Serialize, Deserialize)]
+pub struct TimeScale(pub f64);
+
+impl Default for TimeScale {
+    fn default() -> Self { Self(1.0) }
+}
+
 /// A resource that stores the time since the previous tick.
 #[derive(Default)]
 pub struct DeltaTime(pub f32);
diff --git a/common/state/src/state.rs b/common/state/src/state.rs
index 3464bb01e4..5cc238b242 100644
--- a/common/state/src/state.rs
+++ b/common/state/src/state.rs
@@ -15,7 +15,7 @@ use common::{
     region::RegionMap,
     resources::{
         DeltaTime, EntitiesDiedLastTick, GameMode, PlayerEntity, PlayerPhysicsSettings, Time,
-        TimeOfDay,
+        TimeOfDay, TimeScale,
     },
     shared_server_config::ServerConstants,
     slowjob::SlowJobPool,
@@ -269,6 +269,7 @@ impl State {
         ecs.insert(Calendar::default());
         ecs.insert(WeatherGrid::new(Vec2::zero()));
         ecs.insert(Time(0.0));
+        ecs.insert(TimeScale(1.0));
 
         // Register unsynced resources used by the ECS.
         ecs.insert(DeltaTime(0.0));
@@ -644,14 +645,16 @@ impl State {
         }
 
         // Change the time accordingly.
+        let time_scale = self.ecs.read_resource::<TimeScale>().0;
         self.ecs.write_resource::<TimeOfDay>().0 +=
-            dt.as_secs_f64() * server_constants.day_cycle_coefficient;
-        self.ecs.write_resource::<Time>().0 += dt.as_secs_f64();
+            dt.as_secs_f64() * server_constants.day_cycle_coefficient * time_scale;
+        self.ecs.write_resource::<Time>().0 += dt.as_secs_f64() * time_scale;
 
         // Update delta time.
         // Beyond a delta time of MAX_DELTA_TIME, start lagging to avoid skipping
         // important physics events.
-        self.ecs.write_resource::<DeltaTime>().0 = dt.as_secs_f32().min(MAX_DELTA_TIME);
+        self.ecs.write_resource::<DeltaTime>().0 =
+            (dt.as_secs_f32() * time_scale as f32).min(MAX_DELTA_TIME);
 
         if update_terrain_and_regions {
             self.update_region_map();
diff --git a/rtsim/src/ai/mod.rs b/rtsim/src/ai/mod.rs
index 1bcc653451..2459add657 100644
--- a/rtsim/src/ai/mod.rs
+++ b/rtsim/src/ai/mod.rs
@@ -1,3 +1,7 @@
+pub mod predicate;
+
+use predicate::Predicate;
+
 use crate::{
     data::{
         npc::{Controller, Npc, NpcId},
@@ -15,6 +19,39 @@ use rand_chacha::ChaChaRng;
 use std::{any::Any, collections::VecDeque, marker::PhantomData, ops::ControlFlow};
 use world::{IndexRef, World};
 
+pub trait State: Clone + Send + Sync + 'static {}
+
+impl<T: Clone + Send + Sync + 'static> State for T {}
+
+#[derive(Clone, Copy)]
+struct Resettable<T> {
+    original: T,
+    current: T,
+}
+
+impl<T: Clone> From<T> for Resettable<T> {
+    fn from(value: T) -> Self {
+        Self {
+            original: value.clone(),
+            current: value,
+        }
+    }
+}
+
+impl<T: Clone> Resettable<T> {
+    fn reset(&mut self) { self.current = self.original.clone(); }
+}
+
+impl<T> std::ops::Deref for Resettable<T> {
+    type Target = T;
+
+    fn deref(&self) -> &Self::Target { &self.current }
+}
+
+impl<T> std::ops::DerefMut for Resettable<T> {
+    fn deref_mut(&mut self) -> &mut Self::Target { &mut self.current }
+}
+
 /// The context provided to an [`Action`] while it is being performed. It should
 /// be possible to access any and all important information about the game world
 /// through this struct.
@@ -33,6 +70,8 @@ pub struct NpcCtx<'a> {
     pub sentiments: &'a mut Sentiments,
     pub known_reports: &'a mut HashSet<ReportId>,
 
+    /// The delta time since this npcs ai was last ran.
+    pub dt: f32,
     pub rng: ChaChaRng,
 }
 
@@ -55,7 +94,7 @@ pub struct NpcCtx<'a> {
 /// You should not need to implement this trait yourself when writing AI code.
 /// If you find yourself wanting to implement it, please discuss with the core
 /// dev team first.
-pub trait Action<R = ()>: Any + Send + Sync {
+pub trait Action<S = (), R = ()>: Any + Send + Sync {
     /// Returns `true` if the action should be considered the 'same' (i.e:
     /// achieving the same objective) as another. In general, the AI system
     /// will try to avoid switching (and therefore restarting) tasks when the
@@ -68,7 +107,7 @@ pub trait Action<R = ()>: Any + Send + Sync {
         Self: Sized;
 
     /// Like [`Action::is_same`], but allows for dynamic dispatch.
-    fn dyn_is_same_sized(&self, other: &dyn Action<R>) -> bool
+    fn dyn_is_same_sized(&self, other: &dyn Action<S, R>) -> bool
     where
         Self: Sized,
     {
@@ -79,7 +118,7 @@ pub trait Action<R = ()>: Any + Send + Sync {
     }
 
     /// Like [`Action::is_same`], but allows for dynamic dispatch.
-    fn dyn_is_same(&self, other: &dyn Action<R>) -> bool;
+    fn dyn_is_same(&self, other: &dyn Action<S, R>) -> bool;
 
     /// Generate a backtrace for the action. The action should recursively push
     /// all of the tasks it is currently performing.
@@ -89,7 +128,7 @@ pub trait Action<R = ()>: Any + Send + Sync {
     fn reset(&mut self);
 
     /// Perform the action for the current tick.
-    fn tick(&mut self, ctx: &mut NpcCtx) -> ControlFlow<R>;
+    fn tick(&mut self, ctx: &mut NpcCtx, state: &mut S) -> ControlFlow<R>;
 
     /// Create an action that chains together two sub-actions, one after the
     /// other.
@@ -101,7 +140,7 @@ pub trait Action<R = ()>: Any + Send + Sync {
     /// goto(enemy_npc).then(attack(enemy_npc))
     /// ```
     #[must_use]
-    fn then<A1: Action<R1>, R1>(self, other: A1) -> Then<Self, A1, R>
+    fn then<A1: Action<S, R1>, R1>(self, other: A1) -> Then<Self, A1, R>
     where
         Self: Sized,
     {
@@ -122,7 +161,7 @@ pub trait Action<R = ()>: Any + Send + Sync {
     /// find_and_collect(ChunkResource::Flax).repeat()
     /// ```
     #[must_use]
-    fn repeat<R1>(self) -> Repeat<Self, R1>
+    fn repeat(self) -> Repeat<Self, R>
     where
         Self: Sized,
     {
@@ -138,11 +177,11 @@ pub trait Action<R = ()>: Any + Send + Sync {
     /// go_on_an_adventure().repeat().stop_if(|ctx| ctx.npc.age > 111.0)
     /// ```
     #[must_use]
-    fn stop_if<F: FnMut(&mut NpcCtx) -> bool + Clone>(self, f: F) -> StopIf<Self, F>
+    fn stop_if<P: Predicate + Clone>(self, p: P) -> StopIf<Self, P>
     where
         Self: Sized,
     {
-        StopIf(self, f.clone(), f)
+        StopIf(self, p.into())
     }
 
     /// Pause an action to possibly perform another action.
@@ -159,7 +198,11 @@ pub trait Action<R = ()>: Any + Send + Sync {
     ///     })
     /// ```
     #[must_use]
-    fn interrupt_with<A1: Action<R1>, R1, F: FnMut(&mut NpcCtx) -> Option<A1> + Clone>(
+    fn interrupt_with<
+        A1: Action<S, R1>,
+        R1,
+        F: Fn(&mut NpcCtx, &mut S) -> Option<A1> + Send + Sync + 'static,
+    >(
         self,
         f: F,
     ) -> InterruptWith<Self, F, A1, R1>
@@ -168,8 +211,7 @@ pub trait Action<R = ()>: Any + Send + Sync {
     {
         InterruptWith {
             a0: self,
-            f: f.clone(),
-            f2: f,
+            f,
             a1: None,
             phantom: PhantomData,
         }
@@ -177,7 +219,7 @@ pub trait Action<R = ()>: Any + Send + Sync {
 
     /// Map the completion value of this action to something else.
     #[must_use]
-    fn map<F: FnMut(R) -> R1, R1>(self, f: F) -> Map<Self, F, R>
+    fn map<F: Fn(R, &mut S) -> R1, R1>(self, f: F) -> Map<Self, F, R>
     where
         Self: Sized,
     {
@@ -209,13 +251,54 @@ pub trait Action<R = ()>: Any + Send + Sync {
     /// }
     /// ```
     #[must_use]
-    fn boxed(self) -> Box<dyn Action<R>>
+    fn boxed(self) -> Box<dyn Action<S, R>>
     where
         Self: Sized,
     {
         Box::new(self)
     }
 
+    /// Set the state for child actions.
+    ///
+    /// Note that state is reset when repeated.
+    ///
+    /// # Example
+    ///
+    /// ```ignore
+    /// just(|_, state: &mut i32| *state += 2)
+    ///     // Outputs 5
+    ///     .then(just(|_, state: &mut i32| println!("{state}")))
+    ///     .with_state(3)
+    /// ```
+    #[must_use]
+    fn with_state<S0>(self, s: S) -> WithState<Self, S, S0>
+    where
+        Self: Sized,
+        S: Clone,
+    {
+        WithState(self, s.into(), PhantomData)
+    }
+
+    /// Map the current state for child actions, this map expects the return
+    /// value to have the same lifetime as the input state.
+    ///
+    /// # Example
+    ///
+    /// ```ignore
+    /// // Goes forward 5 steps
+    /// just(|_, state: &mut i32| go_forward(*state))
+    ///     .map_state(|state: &mut (i32, i32)| &mut state.1)
+    ///     .with_state((14, 5))
+    /// ```
+    #[must_use]
+    fn map_state<S0, F>(self, f: F) -> MapState<Self, F, S, S0>
+    where
+        F: Fn(&mut S0) -> &mut S,
+        Self: Sized,
+    {
+        MapState(self, f, PhantomData)
+    }
+
     /// Add debugging information to the action that will be visible when using
     /// the `/npc_info` command.
     ///
@@ -249,10 +332,10 @@ pub trait Action<R = ()>: Any + Send + Sync {
     }
 }
 
-impl<R: 'static> Action<R> for Box<dyn Action<R>> {
+impl<S: State, R: 'static> Action<S, R> for Box<dyn Action<S, R>> {
     fn is_same(&self, other: &Self) -> bool { (**self).dyn_is_same(other) }
 
-    fn dyn_is_same(&self, other: &dyn Action<R>) -> bool {
+    fn dyn_is_same(&self, other: &dyn Action<S, R>) -> bool {
         match (other as &dyn Any).downcast_ref::<Self>() {
             Some(other) => self.is_same(other),
             None => false,
@@ -263,10 +346,12 @@ impl<R: 'static> Action<R> for Box<dyn Action<R>> {
 
     fn reset(&mut self) { (**self).reset(); }
 
-    fn tick(&mut self, ctx: &mut NpcCtx) -> ControlFlow<R> { (**self).tick(ctx) }
+    fn tick(&mut self, ctx: &mut NpcCtx, state: &mut S) -> ControlFlow<R> {
+        (**self).tick(ctx, state)
+    }
 }
 
-impl<R: 'static, A: Action<R>, B: Action<R>> Action<R> for Either<A, B> {
+impl<S: State, R: 'static, A: Action<S, R>, B: Action<S, R>> Action<S, R> for Either<A, B> {
     fn is_same(&self, other: &Self) -> bool {
         match (self, other) {
             (Either::Left(x), Either::Left(y)) => x.is_same(y),
@@ -275,7 +360,7 @@ impl<R: 'static, A: Action<R>, B: Action<R>> Action<R> for Either<A, B> {
         }
     }
 
-    fn dyn_is_same(&self, other: &dyn Action<R>) -> bool { self.dyn_is_same_sized(other) }
+    fn dyn_is_same(&self, other: &dyn Action<S, R>) -> bool { self.dyn_is_same_sized(other) }
 
     fn backtrace(&self, bt: &mut Vec<String>) {
         match self {
@@ -291,10 +376,10 @@ impl<R: 'static, A: Action<R>, B: Action<R>> Action<R> for Either<A, B> {
         }
     }
 
-    fn tick(&mut self, ctx: &mut NpcCtx) -> ControlFlow<R> {
+    fn tick(&mut self, ctx: &mut NpcCtx, state: &mut S) -> ControlFlow<R> {
         match self {
-            Either::Left(x) => x.tick(ctx),
-            Either::Right(x) => x.tick(ctx),
+            Either::Left(x) => x.tick(ctx, state),
+            Either::Right(x) => x.tick(ctx, state),
         }
     }
 }
@@ -305,13 +390,17 @@ impl<R: 'static, A: Action<R>, B: Action<R>> Action<R> for Either<A, B> {
 #[derive(Copy, Clone)]
 pub struct Now<F, A>(F, Option<A>);
 
-impl<R: Send + Sync + 'static, F: FnMut(&mut NpcCtx) -> A + Send + Sync + 'static, A: Action<R>>
-    Action<R> for Now<F, A>
+impl<
+    S: State,
+    R: Send + Sync + 'static,
+    F: Fn(&mut NpcCtx, &mut S) -> A + Send + Sync + 'static,
+    A: Action<S, R>,
+> Action<S, R> for Now<F, A>
 {
     // TODO: This doesn't compare?!
     fn is_same(&self, _other: &Self) -> bool { true }
 
-    fn dyn_is_same(&self, other: &dyn Action<R>) -> bool { self.dyn_is_same_sized(other) }
+    fn dyn_is_same(&self, other: &dyn Action<S, R>) -> bool { self.dyn_is_same_sized(other) }
 
     fn backtrace(&self, bt: &mut Vec<String>) {
         if let Some(action) = &self.1 {
@@ -321,12 +410,11 @@ impl<R: Send + Sync + 'static, F: FnMut(&mut NpcCtx) -> A + Send + Sync + 'stati
         }
     }
 
-    // TODO: Reset closure?
     fn reset(&mut self) { self.1 = None; }
 
     // TODO: Reset closure state?
-    fn tick(&mut self, ctx: &mut NpcCtx) -> ControlFlow<R> {
-        (self.1.get_or_insert_with(|| (self.0)(ctx))).tick(ctx)
+    fn tick(&mut self, ctx: &mut NpcCtx, state: &mut S) -> ControlFlow<R> {
+        (self.1.get_or_insert_with(|| (self.0)(ctx, state))).tick(ctx, state)
     }
 }
 
@@ -342,9 +430,9 @@ impl<R: Send + Sync + 'static, F: FnMut(&mut NpcCtx) -> A + Send + Sync + 'stati
 /// // An action that makes an NPC immediately travel to its *current* home
 /// now(|ctx| goto(ctx.npc.home))
 /// ```
-pub fn now<F, A>(f: F) -> Now<F, A>
+pub fn now<S, R, F, A: Action<S, R>>(f: F) -> Now<F, A>
 where
-    F: FnMut(&mut NpcCtx) -> A,
+    F: Fn(&mut NpcCtx, &mut S) -> A + Send + Sync + 'static,
 {
     Now(f, None)
 }
@@ -356,15 +444,16 @@ where
 pub struct Until<F, A, R>(F, Option<A>, PhantomData<R>);
 
 impl<
+    S: State,
     R: Send + Sync + 'static,
-    F: FnMut(&mut NpcCtx) -> Option<A> + Send + Sync + 'static,
-    A: Action<R>,
-> Action<()> for Until<F, A, R>
+    F: Fn(&mut NpcCtx, &mut S) -> Option<A> + Send + Sync + 'static,
+    A: Action<S, R>,
+> Action<S, ()> for Until<F, A, R>
 {
     // TODO: This doesn't compare?!
     fn is_same(&self, _other: &Self) -> bool { true }
 
-    fn dyn_is_same(&self, other: &dyn Action<()>) -> bool { self.dyn_is_same_sized(other) }
+    fn dyn_is_same(&self, other: &dyn Action<S, ()>) -> bool { self.dyn_is_same_sized(other) }
 
     fn backtrace(&self, bt: &mut Vec<String>) {
         if let Some(action) = &self.1 {
@@ -374,20 +463,18 @@ impl<
         }
     }
 
-    // TODO: Reset closure?
     fn reset(&mut self) { self.1 = None; }
 
-    // TODO: Reset closure state?
-    fn tick(&mut self, ctx: &mut NpcCtx) -> ControlFlow<()> {
+    fn tick(&mut self, ctx: &mut NpcCtx, state: &mut S) -> ControlFlow<()> {
         match &mut self.1 {
-            Some(x) => match x.tick(ctx) {
+            Some(x) => match x.tick(ctx, state) {
                 ControlFlow::Continue(()) => ControlFlow::Continue(()),
                 ControlFlow::Break(_) => {
                     self.1 = None;
                     ControlFlow::Continue(())
                 },
             },
-            None => match (self.0)(ctx) {
+            None => match (self.0)(ctx, state) {
                 Some(x) => {
                     self.1 = Some(x);
                     ControlFlow::Continue(())
@@ -398,9 +485,9 @@ impl<
     }
 }
 
-pub fn until<F, A, R>(f: F) -> Until<F, A, R>
+pub fn until<S, F, A: Action<S, R>, R>(f: F) -> Until<F, A, R>
 where
-    F: FnMut(&mut NpcCtx) -> Option<A>,
+    F: Fn(&mut NpcCtx, &mut S) -> Option<A>,
 {
     Until(f, None, PhantomData)
 }
@@ -411,20 +498,20 @@ where
 #[derive(Copy, Clone)]
 pub struct Just<F, R = ()>(F, PhantomData<R>);
 
-impl<R: Send + Sync + 'static, F: FnMut(&mut NpcCtx) -> R + Send + Sync + 'static> Action<R>
-    for Just<F, R>
+impl<S: State, R: Send + Sync + 'static, F: Fn(&mut NpcCtx, &mut S) -> R + Send + Sync + 'static>
+    Action<S, R> for Just<F, R>
 {
     fn is_same(&self, _other: &Self) -> bool { true }
 
-    fn dyn_is_same(&self, other: &dyn Action<R>) -> bool { self.dyn_is_same_sized(other) }
+    fn dyn_is_same(&self, other: &dyn Action<S, R>) -> bool { self.dyn_is_same_sized(other) }
 
     fn backtrace(&self, _bt: &mut Vec<String>) {}
 
-    // TODO: Reset closure?
     fn reset(&mut self) {}
 
-    // TODO: Reset closure state?
-    fn tick(&mut self, ctx: &mut NpcCtx) -> ControlFlow<R> { ControlFlow::Break((self.0)(ctx)) }
+    fn tick(&mut self, ctx: &mut NpcCtx, state: &mut S) -> ControlFlow<R> {
+        ControlFlow::Break((self.0)(ctx, state))
+    }
 }
 
 /// An action that executes some code just once when performed.
@@ -438,9 +525,9 @@ impl<R: Send + Sync + 'static, F: FnMut(&mut NpcCtx) -> R + Send + Sync + 'stati
 /// // Make the current NPC say 'Hello, world!' exactly once
 /// just(|ctx| ctx.controller.say("Hello, world!"))
 /// ```
-pub fn just<F, R: Send + Sync + 'static>(f: F) -> Just<F, R>
+pub fn just<S: State, F, R: Send + Sync + 'static>(f: F) -> Just<F, R>
 where
-    F: FnMut(&mut NpcCtx) -> R + Send + Sync + 'static,
+    F: Fn(&mut NpcCtx, &mut S) -> R + Send + Sync + 'static,
 {
     Just(f, PhantomData)
 }
@@ -451,16 +538,18 @@ where
 #[derive(Copy, Clone)]
 pub struct Finish;
 
-impl Action<()> for Finish {
+impl<S: State> Action<S, ()> for Finish {
     fn is_same(&self, _other: &Self) -> bool { true }
 
-    fn dyn_is_same(&self, other: &dyn Action<()>) -> bool { self.dyn_is_same_sized(other) }
+    fn dyn_is_same(&self, other: &dyn Action<S, ()>) -> bool { self.dyn_is_same_sized(other) }
 
     fn backtrace(&self, _bt: &mut Vec<String>) {}
 
     fn reset(&mut self) {}
 
-    fn tick(&mut self, _ctx: &mut NpcCtx) -> ControlFlow<()> { ControlFlow::Break(()) }
+    fn tick(&mut self, _ctx: &mut NpcCtx, _state: &mut S) -> ControlFlow<()> {
+        ControlFlow::Break(())
+    }
 }
 
 /// An action that immediately finishes without doing anything.
@@ -492,33 +581,33 @@ pub const URGENT: Priority = 0;
 pub const IMPORTANT: Priority = 1;
 pub const CASUAL: Priority = 2;
 
-pub struct Node<R>(Box<dyn Action<R>>, Priority);
+pub struct Node<S, R>(Box<dyn Action<S, R>>, Priority);
 
 /// Perform an action with [`URGENT`] priority (see [`choose`]).
 #[must_use]
-pub fn urgent<A: Action<R>, R>(a: A) -> Node<R> { Node(Box::new(a), URGENT) }
+pub fn urgent<S, A: Action<S, R>, R>(a: A) -> Node<S, R> { Node(Box::new(a), URGENT) }
 
 /// Perform an action with [`IMPORTANT`] priority (see [`choose`]).
 #[must_use]
-pub fn important<A: Action<R>, R>(a: A) -> Node<R> { Node(Box::new(a), IMPORTANT) }
+pub fn important<S, A: Action<S, R>, R>(a: A) -> Node<S, R> { Node(Box::new(a), IMPORTANT) }
 
 /// Perform an action with [`CASUAL`] priority (see [`choose`]).
 #[must_use]
-pub fn casual<A: Action<R>, R>(a: A) -> Node<R> { Node(Box::new(a), CASUAL) }
+pub fn casual<S, A: Action<S, R>, R>(a: A) -> Node<S, R> { Node(Box::new(a), CASUAL) }
 
 /// See [`choose`] and [`watch`].
-pub struct Tree<F, R> {
+pub struct Tree<S, F, R> {
     next: F,
-    prev: Option<Node<R>>,
+    prev: Option<Node<S, R>>,
     interrupt: bool,
 }
 
-impl<F: FnMut(&mut NpcCtx) -> Node<R> + Send + Sync + 'static, R: 'static> Action<R>
-    for Tree<F, R>
+impl<S: State, F: Fn(&mut NpcCtx, &mut S) -> Node<S, R> + Send + Sync + 'static, R: 'static>
+    Action<S, R> for Tree<S, F, R>
 {
     fn is_same(&self, _other: &Self) -> bool { true }
 
-    fn dyn_is_same(&self, other: &dyn Action<R>) -> bool { self.dyn_is_same_sized(other) }
+    fn dyn_is_same(&self, other: &dyn Action<S, R>) -> bool { self.dyn_is_same_sized(other) }
 
     fn backtrace(&self, bt: &mut Vec<String>) {
         if let Some(prev) = &self.prev {
@@ -530,9 +619,8 @@ impl<F: FnMut(&mut NpcCtx) -> Node<R> + Send + Sync + 'static, R: 'static> Actio
 
     fn reset(&mut self) { self.prev = None; }
 
-    // TODO: Reset `next` too?
-    fn tick(&mut self, ctx: &mut NpcCtx) -> ControlFlow<R> {
-        let new = (self.next)(ctx);
+    fn tick(&mut self, ctx: &mut NpcCtx, state: &mut S) -> ControlFlow<R> {
+        let new = (self.next)(ctx, state);
 
         let prev = match &mut self.prev {
             Some(prev) if prev.1 <= new.1 && (prev.0.dyn_is_same(&*new.0) || !self.interrupt) => {
@@ -541,7 +629,7 @@ impl<F: FnMut(&mut NpcCtx) -> Node<R> + Send + Sync + 'static, R: 'static> Actio
             _ => self.prev.insert(new),
         };
 
-        match prev.0.tick(ctx) {
+        match prev.0.tick(ctx, state) {
             ControlFlow::Continue(()) => ControlFlow::Continue(()),
             ControlFlow::Break(r) => {
                 self.prev = None;
@@ -575,9 +663,9 @@ impl<F: FnMut(&mut NpcCtx) -> Node<R> + Send + Sync + 'static, R: 'static> Actio
 /// })
 /// ```
 #[must_use]
-pub fn choose<R: 'static, F>(f: F) -> impl Action<R>
+pub fn choose<S: State, R: 'static, F>(f: F) -> impl Action<S, R>
 where
-    F: FnMut(&mut NpcCtx) -> Node<R> + Send + Sync + 'static,
+    F: Fn(&mut NpcCtx, &mut S) -> Node<S, R> + Send + Sync + 'static,
 {
     Tree {
         next: f,
@@ -610,9 +698,9 @@ where
 /// })
 /// ```
 #[must_use]
-pub fn watch<R: 'static, F>(f: F) -> impl Action<R>
+pub fn watch<S: State, R: 'static, F>(f: F) -> impl Action<S, R>
 where
-    F: FnMut(&mut NpcCtx) -> Node<R> + Send + Sync + 'static,
+    F: Fn(&mut NpcCtx, &mut S) -> Node<S, R> + Send + Sync + 'static,
 {
     Tree {
         next: f,
@@ -632,14 +720,19 @@ pub struct Then<A0, A1, R0> {
     phantom: PhantomData<R0>,
 }
 
-impl<A0: Action<R0>, A1: Action<R1>, R0: Send + Sync + 'static, R1: Send + Sync + 'static>
-    Action<R1> for Then<A0, A1, R0>
+impl<
+    S: State,
+    A0: Action<S, R0>,
+    A1: Action<S, R1>,
+    R0: Send + Sync + 'static,
+    R1: Send + Sync + 'static,
+> Action<S, R1> for Then<A0, A1, R0>
 {
     fn is_same(&self, other: &Self) -> bool {
         self.a0.is_same(&other.a0) && self.a1.is_same(&other.a1)
     }
 
-    fn dyn_is_same(&self, other: &dyn Action<R1>) -> bool { self.dyn_is_same_sized(other) }
+    fn dyn_is_same(&self, other: &dyn Action<S, R1>) -> bool { self.dyn_is_same_sized(other) }
 
     fn backtrace(&self, bt: &mut Vec<String>) {
         if self.a0_finished {
@@ -655,14 +748,14 @@ impl<A0: Action<R0>, A1: Action<R1>, R0: Send + Sync + 'static, R1: Send + Sync
         self.a1.reset();
     }
 
-    fn tick(&mut self, ctx: &mut NpcCtx) -> ControlFlow<R1> {
+    fn tick(&mut self, ctx: &mut NpcCtx, state: &mut S) -> ControlFlow<R1> {
         if !self.a0_finished {
-            match self.a0.tick(ctx) {
+            match self.a0.tick(ctx, state) {
                 ControlFlow::Continue(()) => return ControlFlow::Continue(()),
                 ControlFlow::Break(_) => self.a0_finished = true,
             }
         }
-        self.a1.tick(ctx)
+        self.a1.tick(ctx, state)
     }
 }
 
@@ -673,22 +766,22 @@ impl<A0: Action<R0>, A1: Action<R1>, R0: Send + Sync + 'static, R1: Send + Sync
 pub struct InterruptWith<A0, F, A1, R1> {
     a0: A0,
     f: F,
-    f2: F,
     a1: Option<A1>,
     phantom: PhantomData<R1>,
 }
 
 impl<
-    A0: Action<R0>,
-    A1: Action<R1>,
-    F: FnMut(&mut NpcCtx) -> Option<A1> + Clone + Send + Sync + 'static,
+    S: State,
+    A0: Action<S, R0>,
+    A1: Action<S, R1>,
+    F: Fn(&mut NpcCtx, &mut S) -> Option<A1> + Send + Sync + 'static,
     R0: Send + Sync + 'static,
     R1: Send + Sync + 'static,
-> Action<R0> for InterruptWith<A0, F, A1, R1>
+> Action<S, R0> for InterruptWith<A0, F, A1, R1>
 {
     fn is_same(&self, other: &Self) -> bool { self.a0.is_same(&other.a0) }
 
-    fn dyn_is_same(&self, other: &dyn Action<R0>) -> bool { self.dyn_is_same_sized(other) }
+    fn dyn_is_same(&self, other: &dyn Action<S, R0>) -> bool { self.dyn_is_same_sized(other) }
 
     fn backtrace(&self, bt: &mut Vec<String>) {
         if let Some(a1) = &self.a1 {
@@ -702,23 +795,22 @@ impl<
 
     fn reset(&mut self) {
         self.a0.reset();
-        self.f = self.f2.clone();
         self.a1 = None;
     }
 
-    fn tick(&mut self, ctx: &mut NpcCtx) -> ControlFlow<R0> {
-        if let Some(new_a1) = (self.f)(ctx) {
+    fn tick(&mut self, ctx: &mut NpcCtx, state: &mut S) -> ControlFlow<R0> {
+        if let Some(new_a1) = (self.f)(ctx, state) {
             self.a1 = Some(new_a1);
         }
 
         if let Some(a1) = &mut self.a1 {
-            match a1.tick(ctx) {
+            match a1.tick(ctx, state) {
                 ControlFlow::Continue(()) => return ControlFlow::Continue(()),
                 ControlFlow::Break(_) => self.a1 = None,
             }
         }
 
-        self.a0.tick(ctx)
+        self.a0.tick(ctx, state)
     }
 }
 
@@ -728,17 +820,17 @@ impl<
 #[derive(Copy, Clone)]
 pub struct Repeat<A, R = ()>(A, PhantomData<R>);
 
-impl<R: Send + Sync + 'static, A: Action<R>> Action<!> for Repeat<A, R> {
+impl<S: State, R: Send + Sync + 'static, A: Action<S, R>> Action<S, !> for Repeat<A, R> {
     fn is_same(&self, other: &Self) -> bool { self.0.is_same(&other.0) }
 
-    fn dyn_is_same(&self, other: &dyn Action<!>) -> bool { self.dyn_is_same_sized(other) }
+    fn dyn_is_same(&self, other: &dyn Action<S, !>) -> bool { self.dyn_is_same_sized(other) }
 
     fn backtrace(&self, bt: &mut Vec<String>) { self.0.backtrace(bt); }
 
     fn reset(&mut self) { self.0.reset(); }
 
-    fn tick(&mut self, ctx: &mut NpcCtx) -> ControlFlow<!> {
-        match self.0.tick(ctx) {
+    fn tick(&mut self, ctx: &mut NpcCtx, state: &mut S) -> ControlFlow<!> {
+        match self.0.tick(ctx, state) {
             ControlFlow::Continue(()) => ControlFlow::Continue(()),
             ControlFlow::Break(_) => {
                 self.0.reset();
@@ -752,17 +844,21 @@ impl<R: Send + Sync + 'static, A: Action<R>> Action<!> for Repeat<A, R> {
 
 /// See [`seq`].
 #[derive(Copy, Clone)]
-pub struct Sequence<I, A, R = ()>(I, I, Option<A>, PhantomData<R>);
+pub struct Sequence<I, A, R = ()>(Resettable<I>, Option<A>, PhantomData<R>);
 
-impl<R: Send + Sync + 'static, I: Iterator<Item = A> + Clone + Send + Sync + 'static, A: Action<R>>
-    Action<()> for Sequence<I, A, R>
+impl<
+    S: State,
+    R: Send + Sync + 'static,
+    I: Iterator<Item = A> + Clone + Send + Sync + 'static,
+    A: Action<S, R>,
+> Action<S, ()> for Sequence<I, A, R>
 {
     fn is_same(&self, _other: &Self) -> bool { true }
 
-    fn dyn_is_same(&self, other: &dyn Action<()>) -> bool { self.dyn_is_same_sized(other) }
+    fn dyn_is_same(&self, other: &dyn Action<S, ()>) -> bool { self.dyn_is_same_sized(other) }
 
     fn backtrace(&self, bt: &mut Vec<String>) {
-        if let Some(action) = &self.2 {
+        if let Some(action) = &self.1 {
             action.backtrace(bt);
         } else {
             bt.push("<thinking>".to_string());
@@ -770,22 +866,22 @@ impl<R: Send + Sync + 'static, I: Iterator<Item = A> + Clone + Send + Sync + 'st
     }
 
     fn reset(&mut self) {
-        self.0 = self.1.clone();
-        self.2 = None;
+        self.0.reset();
+        self.1 = None;
     }
 
-    fn tick(&mut self, ctx: &mut NpcCtx) -> ControlFlow<()> {
-        let item = if let Some(prev) = &mut self.2 {
+    fn tick(&mut self, ctx: &mut NpcCtx, state: &mut S) -> ControlFlow<()> {
+        let item = if let Some(prev) = &mut self.1 {
             prev
         } else {
             match self.0.next() {
-                Some(next) => self.2.insert(next),
+                Some(next) => self.1.insert(next),
                 None => return ControlFlow::Break(()),
             }
         };
 
-        if let ControlFlow::Break(_) = item.tick(ctx) {
-            self.2 = None;
+        if let ControlFlow::Break(_) = item.tick(ctx, state) {
+            self.1 = None;
         }
 
         ControlFlow::Continue(())
@@ -811,39 +907,41 @@ impl<R: Send + Sync + 'static, I: Iterator<Item = A> + Clone + Send + Sync + 'st
 ///     .map(|enemy| attack(enemy)))
 /// ```
 #[must_use]
-pub fn seq<I, A, R>(iter: I) -> Sequence<I, A, R>
+pub fn seq<S, I, A, R>(iter: I) -> Sequence<I, A, R>
 where
     I: Iterator<Item = A> + Clone,
-    A: Action<R>,
+    A: Action<S, R>,
 {
-    Sequence(iter.clone(), iter, None, PhantomData)
+    Sequence(iter.into(), None, PhantomData)
 }
 
 // StopIf
 
 /// See [`Action::stop_if`].
 #[derive(Copy, Clone)]
-pub struct StopIf<A, F>(A, F, F);
+pub struct StopIf<A, P>(A, Resettable<P>);
 
-impl<A: Action<R>, F: FnMut(&mut NpcCtx) -> bool + Clone + Send + Sync + 'static, R>
-    Action<Option<R>> for StopIf<A, F>
+impl<S: State, A: Action<S, R>, P: Predicate + Clone + Send + Sync + 'static, R>
+    Action<S, Option<R>> for StopIf<A, P>
 {
     fn is_same(&self, other: &Self) -> bool { self.0.is_same(&other.0) }
 
-    fn dyn_is_same(&self, other: &dyn Action<Option<R>>) -> bool { self.dyn_is_same_sized(other) }
+    fn dyn_is_same(&self, other: &dyn Action<S, Option<R>>) -> bool {
+        self.dyn_is_same_sized(other)
+    }
 
     fn backtrace(&self, bt: &mut Vec<String>) { self.0.backtrace(bt); }
 
     fn reset(&mut self) {
         self.0.reset();
-        self.1 = self.2.clone();
+        self.1.reset();
     }
 
-    fn tick(&mut self, ctx: &mut NpcCtx) -> ControlFlow<Option<R>> {
-        if (self.1)(ctx) {
+    fn tick(&mut self, ctx: &mut NpcCtx, state: &mut S) -> ControlFlow<Option<R>> {
+        if self.1.should(ctx) {
             ControlFlow::Break(None)
         } else {
-            self.0.tick(ctx).map_break(Some)
+            self.0.tick(ctx, state).map_break(Some)
         }
     }
 }
@@ -854,19 +952,24 @@ impl<A: Action<R>, F: FnMut(&mut NpcCtx) -> bool + Clone + Send + Sync + 'static
 #[derive(Copy, Clone)]
 pub struct Map<A, F, R>(A, F, PhantomData<R>);
 
-impl<A: Action<R>, F: FnMut(R) -> R1 + Send + Sync + 'static, R: Send + Sync + 'static, R1>
-    Action<R1> for Map<A, F, R>
+impl<
+    S: State,
+    A: Action<S, R>,
+    F: Fn(R, &mut S) -> R1 + Send + Sync + 'static,
+    R: Send + Sync + 'static,
+    R1,
+> Action<S, R1> for Map<A, F, R>
 {
     fn is_same(&self, other: &Self) -> bool { self.0.is_same(&other.0) }
 
-    fn dyn_is_same(&self, other: &dyn Action<R1>) -> bool { self.dyn_is_same_sized(other) }
+    fn dyn_is_same(&self, other: &dyn Action<S, R1>) -> bool { self.dyn_is_same_sized(other) }
 
     fn backtrace(&self, bt: &mut Vec<String>) { self.0.backtrace(bt); }
 
     fn reset(&mut self) { self.0.reset(); }
 
-    fn tick(&mut self, ctx: &mut NpcCtx) -> ControlFlow<R1> {
-        self.0.tick(ctx).map_break(&mut self.1)
+    fn tick(&mut self, ctx: &mut NpcCtx, state: &mut S) -> ControlFlow<R1> {
+        self.0.tick(ctx, state).map_break(|t| (self.1)(t, state))
     }
 }
 
@@ -877,15 +980,16 @@ impl<A: Action<R>, F: FnMut(R) -> R1 + Send + Sync + 'static, R: Send + Sync + '
 pub struct Debug<A, F, T>(A, F, PhantomData<T>);
 
 impl<
-    A: Action<R>,
+    S: 'static,
+    A: Action<S, R>,
     F: Fn() -> T + Send + Sync + 'static,
     R: Send + Sync + 'static,
     T: Send + Sync + std::fmt::Display + 'static,
-> Action<R> for Debug<A, F, T>
+> Action<S, R> for Debug<A, F, T>
 {
     fn is_same(&self, other: &Self) -> bool { self.0.is_same(&other.0) }
 
-    fn dyn_is_same(&self, other: &dyn Action<R>) -> bool { self.dyn_is_same_sized(other) }
+    fn dyn_is_same(&self, other: &dyn Action<S, R>) -> bool { self.dyn_is_same_sized(other) }
 
     fn backtrace(&self, bt: &mut Vec<String>) {
         bt.push((self.1)().to_string());
@@ -894,5 +998,56 @@ impl<
 
     fn reset(&mut self) { self.0.reset(); }
 
-    fn tick(&mut self, ctx: &mut NpcCtx) -> ControlFlow<R> { self.0.tick(ctx) }
+    fn tick(&mut self, ctx: &mut NpcCtx, state: &mut S) -> ControlFlow<R> {
+        self.0.tick(ctx, state)
+    }
+}
+
+#[derive(Copy, Clone)]
+pub struct WithState<A, S, S0>(A, Resettable<S>, PhantomData<S0>);
+
+impl<S0: State, S: State, R, A: Action<S, R>> Action<S0, R> for WithState<A, S, S0> {
+    fn is_same(&self, other: &Self) -> bool
+    where
+        Self: Sized,
+    {
+        self.0.is_same(&other.0)
+    }
+
+    fn dyn_is_same(&self, other: &dyn Action<S0, R>) -> bool { self.dyn_is_same_sized(other) }
+
+    fn backtrace(&self, bt: &mut Vec<String>) { self.0.backtrace(bt) }
+
+    fn reset(&mut self) {
+        self.0.reset();
+        self.1.reset();
+    }
+
+    fn tick(&mut self, ctx: &mut NpcCtx, _state: &mut S0) -> ControlFlow<R> {
+        self.0.tick(ctx, &mut self.1.current)
+    }
+}
+
+#[derive(Copy, Clone)]
+pub struct MapState<A, F, S, S0>(A, F, PhantomData<(S, S0)>);
+
+impl<S0: State, S: State, R, A: Action<S, R>, F: Fn(&mut S0) -> &mut S + Send + Sync + 'static>
+    Action<S0, R> for MapState<A, F, S, S0>
+{
+    fn is_same(&self, other: &Self) -> bool
+    where
+        Self: Sized,
+    {
+        self.0.is_same(&other.0)
+    }
+
+    fn dyn_is_same(&self, other: &dyn Action<S0, R>) -> bool { self.dyn_is_same_sized(other) }
+
+    fn backtrace(&self, bt: &mut Vec<String>) { self.0.backtrace(bt) }
+
+    fn reset(&mut self) { self.0.reset(); }
+
+    fn tick(&mut self, ctx: &mut NpcCtx, state: &mut S0) -> ControlFlow<R> {
+        self.0.tick(ctx, (self.1)(state))
+    }
 }
diff --git a/rtsim/src/ai/predicate.rs b/rtsim/src/ai/predicate.rs
new file mode 100644
index 0000000000..99ce0569c3
--- /dev/null
+++ b/rtsim/src/ai/predicate.rs
@@ -0,0 +1,93 @@
+use rand::Rng;
+
+use super::NpcCtx;
+
+pub trait Predicate: Sized + Clone {
+    fn should(&mut self, ctx: &mut NpcCtx) -> bool;
+
+    fn chance(self, chance: f32) -> Chance<Self> {
+        Chance {
+            predicate: self,
+            chance,
+        }
+    }
+
+    /// Hint for when this will be true.
+    fn time_hint(&self) -> Option<f32> { None }
+}
+
+#[derive(Clone, Copy)]
+pub struct Yes;
+
+impl Predicate for Yes {
+    fn should(&mut self, _ctx: &mut NpcCtx) -> bool { true }
+
+    fn time_hint(&self) -> Option<f32> { Some(0.0) }
+}
+
+#[derive(Clone)]
+pub struct EveryRange {
+    next: Option<f32>,
+    sample: std::ops::Range<f32>,
+}
+
+pub fn every_range(r: std::ops::Range<f32>) -> EveryRange {
+    EveryRange {
+        next: None,
+        sample: r,
+    }
+}
+
+impl Predicate for EveryRange {
+    fn should(&mut self, ctx: &mut NpcCtx) -> bool {
+        if let Some(ref mut next) = self.next {
+            *next -= ctx.dt;
+            if *next <= 0.0 {
+                *next += ctx.rng.gen_range(self.sample.clone());
+                true
+            } else {
+                false
+            }
+        } else {
+            self.next = Some(ctx.rng.gen_range(self.sample.clone()));
+            false
+        }
+    }
+
+    fn time_hint(&self) -> Option<f32> { self.next }
+}
+
+#[derive(Clone, Copy)]
+pub struct Chance<P> {
+    predicate: P,
+    chance: f32,
+}
+
+impl<P: Predicate> Predicate for Chance<P> {
+    fn should(&mut self, ctx: &mut NpcCtx) -> bool {
+        self.predicate.should(ctx) && ctx.rng.gen_bool(self.chance as f64)
+    }
+
+    fn time_hint(&self) -> Option<f32> { self.predicate.time_hint() }
+}
+
+impl<F: Fn(&mut NpcCtx) -> bool + Clone> Predicate for F {
+    fn should(&mut self, ctx: &mut NpcCtx) -> bool { self(ctx) }
+}
+
+// Seconds
+pub fn timeout(time: f64) -> Timeout { Timeout { seconds_left: time } }
+
+#[derive(Clone, Copy)]
+pub struct Timeout {
+    seconds_left: f64,
+}
+
+impl Predicate for Timeout {
+    fn should(&mut self, ctx: &mut NpcCtx) -> bool {
+        self.seconds_left -= ctx.dt as f64;
+        self.seconds_left <= 0.0
+    }
+
+    fn time_hint(&self) -> Option<f32> { Some(self.seconds_left.max(0.0) as f32) }
+}
diff --git a/rtsim/src/data/mod.rs b/rtsim/src/data/mod.rs
index 21bda16f54..a2adede9a7 100644
--- a/rtsim/src/data/mod.rs
+++ b/rtsim/src/data/mod.rs
@@ -29,7 +29,7 @@ use std::{
 /// Note that this number does *not* need incrementing on every change: most
 /// field removals/additions are fine. This number should only be incremented
 /// when we wish to perform a *hard purge* of rtsim data.
-pub const CURRENT_VERSION: u32 = 2;
+pub const CURRENT_VERSION: u32 = 3;
 
 #[derive(Clone, Serialize, Deserialize)]
 pub struct Data {
diff --git a/rtsim/src/data/npc.rs b/rtsim/src/data/npc.rs
index 0e5ce66952..b6b707180e 100644
--- a/rtsim/src/data/npc.rs
+++ b/rtsim/src/data/npc.rs
@@ -86,7 +86,7 @@ impl Controller {
 }
 
 pub struct Brain {
-    pub action: Box<dyn Action<!>>,
+    pub action: Box<dyn Action<(), !>>,
 }
 
 #[derive(Serialize, Deserialize)]
diff --git a/rtsim/src/event.rs b/rtsim/src/event.rs
index 4edd6a1f1b..827fca56cc 100644
--- a/rtsim/src/event.rs
+++ b/rtsim/src/event.rs
@@ -1,7 +1,8 @@
 use crate::{RtState, Rule};
 use common::{
+    mounting::VolumePos,
     resources::{Time, TimeOfDay},
-    rtsim::Actor,
+    rtsim::{Actor, VehicleId},
 };
 use vek::*;
 use world::{IndexRef, World};
@@ -36,3 +37,10 @@ pub struct OnDeath {
     pub killer: Option<Actor>,
 }
 impl Event for OnDeath {}
+
+#[derive(Clone)]
+pub struct OnMountVolume {
+    pub actor: Actor,
+    pub pos: VolumePos<VehicleId>,
+}
+impl Event for OnMountVolume {}
diff --git a/rtsim/src/lib.rs b/rtsim/src/lib.rs
index 14844c1e6c..0799d13eff 100644
--- a/rtsim/src/lib.rs
+++ b/rtsim/src/lib.rs
@@ -7,7 +7,10 @@
     trait_upcasting,
     control_flow_enum,
     let_chains,
-    binary_heap_drain_sorted
+    binary_heap_drain_sorted,
+    fn_traits,
+    unboxed_closures,
+    tuple_trait
 )]
 
 pub mod ai;
diff --git a/rtsim/src/rule/npc_ai.rs b/rtsim/src/rule/npc_ai.rs
index fd747beaf6..21929e6be5 100644
--- a/rtsim/src/rule/npc_ai.rs
+++ b/rtsim/src/rule/npc_ai.rs
@@ -1,7 +1,11 @@
-use std::hash::BuildHasherDefault;
+use std::{collections::VecDeque, hash::BuildHasherDefault};
 
 use crate::{
-    ai::{casual, choose, finish, important, just, now, seq, until, Action, NpcCtx},
+    ai::{
+        casual, choose, finish, important, just, now,
+        predicate::{every_range, timeout, Chance, EveryRange, Predicate},
+        seq, until, Action, NpcCtx, State,
+    },
     data::{
         npc::{Brain, PathData, SimulationMode},
         ReportKind, Sentiment, Sites,
@@ -52,6 +56,12 @@ const CARDINALS: &[Vec2<i32>] = &[
     Vec2::new(0, -1),
 ];
 
+#[derive(Clone)]
+struct DefaultState {
+    socialize_timer: EveryRange,
+    move_home_timer: Chance<EveryRange>,
+}
+
 fn path_in_site(start: Vec2<i32>, end: Vec2<i32>, site: &site2::Site) -> PathResult<Vec2<i32>> {
     let heuristic = |tile: &Vec2<i32>, _: &Vec2<i32>| tile.as_::<f32>().distance(end.as_());
     let mut astar = Astar::new(1000, start, BuildHasherDefault::<FxHasher64>::default());
@@ -222,7 +232,17 @@ fn path_towns(
 
 impl Rule for NpcAi {
     fn start(rtstate: &mut RtState) -> Result<Self, RuleError> {
-        rtstate.bind::<Self, OnTick>(|ctx| {
+        // Keep track of the last `SIMULATED_TICK_SKIP` ticks, to know the deltatime
+        // since the last tick we ran the npc.
+        let mut last_ticks: VecDeque<_> = [1.0 / 30.0; SIMULATED_TICK_SKIP as usize]
+            .into_iter()
+            .collect();
+
+        rtstate.bind::<Self, OnTick>(move |ctx| {
+            last_ticks.push_front(ctx.event.dt);
+            if last_ticks.len() >= SIMULATED_TICK_SKIP as usize {
+                last_ticks.pop_back();
+            }
             // Temporarily take the brains of NPCs out of their heads to appease the borrow
             // checker
             let mut npc_data = {
@@ -239,13 +259,20 @@ impl Rule for NpcAi {
                         let sentiments = std::mem::take(&mut npc.sentiments);
                         let known_reports = std::mem::take(&mut npc.known_reports);
                         let brain = npc.brain.take().unwrap_or_else(|| Brain {
-                            action: Box::new(think().repeat()),
+                            action: Box::new(think().repeat().with_state(DefaultState {
+                                socialize_timer: every_range(15.0..30.0),
+                                move_home_timer: every_range(400.0..2000.0).chance(0.5),
+                            })),
                         });
                         (npc_id, controller, inbox, sentiments, known_reports, brain)
                     })
                     .collect::<Vec<_>>()
             };
 
+            // The sum of the last `SIMULATED_TICK_SKIP` tick deltatimes is the deltatime since 
+            // simulated npcs ran this tick had their ai ran.
+            let simulated_dt = last_ticks.iter().sum::<f32>();
+
             // Do a little thinking
             {
                 let data = &*ctx.state.data();
@@ -267,8 +294,13 @@ impl Rule for NpcAi {
                             inbox,
                             known_reports,
                             sentiments,
+                            dt: if matches!(npc.mode, SimulationMode::Loaded) {
+                                ctx.event.dt
+                            } else {
+                                simulated_dt
+                            },
                             rng: ChaChaRng::from_seed(thread_rng().gen::<[u8; 32]>()),
-                        });
+                        }, &mut ());
                     });
             }
 
@@ -287,20 +319,19 @@ impl Rule for NpcAi {
     }
 }
 
-fn idle() -> impl Action { just(|ctx| ctx.controller.do_idle()).debug(|| "idle") }
+fn idle<S: State>() -> impl Action<S> { just(|ctx, _| ctx.controller.do_idle()).debug(|| "idle") }
 
 /// Try to walk toward a 3D position without caring for obstacles.
-fn goto(wpos: Vec3<f32>, speed_factor: f32, goal_dist: f32) -> impl Action {
+fn goto<S: State>(wpos: Vec3<f32>, speed_factor: f32, goal_dist: f32) -> impl Action<S> {
     const STEP_DIST: f32 = 24.0;
     const WAYPOINT_DIST: f32 = 12.0;
-    let mut waypoint = None;
 
-    just(move |ctx| {
+    just(move |ctx, waypoint: &mut Option<Vec3<f32>>| {
         // If we're close to the next waypoint, complete it
         if waypoint.map_or(false, |waypoint: Vec3<f32>| {
             ctx.npc.wpos.xy().distance_squared(waypoint.xy()) < WAYPOINT_DIST.powi(2)
         }) {
-            waypoint = None;
+            *waypoint = None;
         }
 
         // Get the next waypoint on the route toward the goal
@@ -309,40 +340,36 @@ fn goto(wpos: Vec3<f32>, speed_factor: f32, goal_dist: f32) -> impl Action {
             let len = rpos.magnitude();
             let wpos = ctx.npc.wpos + (rpos / len) * len.min(STEP_DIST);
 
-            wpos.with_z(
-                ctx.world
-                    .sim()
-                    .get_surface_alt_approx(wpos.xy().as_())
-                    .unwrap_or(wpos.z),
-            )
+            wpos.with_z(ctx.world.sim().get_surface_alt_approx(wpos.xy().as_()))
         });
 
         ctx.controller.do_goto(*waypoint, speed_factor);
     })
     .repeat()
-    .stop_if(move |ctx| ctx.npc.wpos.xy().distance_squared(wpos.xy()) < goal_dist.powi(2))
+    .stop_if(move |ctx: &mut NpcCtx| {
+        ctx.npc.wpos.xy().distance_squared(wpos.xy()) < goal_dist.powi(2)
+    })
+    .with_state(None)
     .debug(move || format!("goto {}, {}, {}", wpos.x, wpos.y, wpos.z))
-    .map(|_| {})
+    .map(|_, _| {})
 }
 
 /// Try to walk fly a 3D position following the terrain altitude at an offset
 /// without caring for obstacles.
-fn goto_flying(
+fn goto_flying<S: State>(
     wpos: Vec3<f32>,
     speed_factor: f32,
     goal_dist: f32,
     step_dist: f32,
     waypoint_dist: f32,
     height_offset: f32,
-) -> impl Action {
-    let mut waypoint = None;
-
-    just(move |ctx| {
+) -> impl Action<S> {
+    just(move |ctx, waypoint: &mut Option<Vec3<f32>>| {
         // If we're close to the next waypoint, complete it
         if waypoint.map_or(false, |waypoint: Vec3<f32>| {
             ctx.npc.wpos.distance_squared(waypoint) < waypoint_dist.powi(2)
         }) {
-            waypoint = None;
+            *waypoint = None;
         }
 
         // Get the next waypoint on the route toward the goal
@@ -351,43 +378,41 @@ fn goto_flying(
             let len = rpos.magnitude();
             let wpos = ctx.npc.wpos + (rpos / len) * len.min(step_dist);
 
-            wpos.with_z(
-                ctx.world
-                    .sim()
-                    .get_surface_alt_approx(wpos.xy().as_())
-                    .map(|alt| alt + height_offset)
-                    .unwrap_or(wpos.z),
-            )
+            wpos.with_z(ctx.world.sim().get_surface_alt_approx(wpos.xy().as_()) + height_offset)
         });
 
         ctx.controller.do_goto(*waypoint, speed_factor);
     })
     .repeat()
-    .stop_if(move |ctx| ctx.npc.wpos.xy().distance_squared(wpos.xy()) < goal_dist.powi(2))
+    .boxed()
+    .with_state(None)
+    .stop_if(move |ctx: &mut NpcCtx| {
+        ctx.npc.wpos.xy().distance_squared(wpos.xy()) < goal_dist.powi(2)
+    })
     .debug(move || format!("goto {}, {}, {}", wpos.x, wpos.y, wpos.z))
-    .map(|_| {})
+    .map(|_, _| {})
 }
 
-/// Try to walk toward a 2D position on the terrain without caring for
+/// Try to walk toward a 2D position on the surface without caring for
 /// obstacles.
-fn goto_2d(wpos2d: Vec2<f32>, speed_factor: f32, goal_dist: f32) -> impl Action {
-    now(move |ctx| {
-        let wpos = wpos2d.with_z(ctx.world.sim().get_alt_approx(wpos2d.as_()).unwrap_or(0.0));
+fn goto_2d<S: State>(wpos2d: Vec2<f32>, speed_factor: f32, goal_dist: f32) -> impl Action<S> {
+    now(move |ctx, _| {
+        let wpos = wpos2d.with_z(ctx.world.sim().get_surface_alt_approx(wpos2d.as_()));
         goto(wpos, speed_factor, goal_dist)
     })
 }
 
 /// Try to fly toward a 2D position following the terrain altitude at an offset
 /// without caring for obstacles.
-fn goto_2d_flying(
+fn goto_2d_flying<S: State>(
     wpos2d: Vec2<f32>,
     speed_factor: f32,
     goal_dist: f32,
     step_dist: f32,
     waypoint_dist: f32,
     height_offset: f32,
-) -> impl Action {
-    now(move |ctx| {
+) -> impl Action<S> {
+    now(move |ctx, _| {
         let wpos = wpos2d
             .with_z(ctx.world.sim().get_alt_approx(wpos2d.as_()).unwrap_or(0.0) + height_offset);
         goto_flying(
@@ -401,11 +426,11 @@ fn goto_2d_flying(
     })
 }
 
-fn traverse_points<F>(mut next_point: F, speed_factor: f32) -> impl Action
+fn traverse_points<S: State, F>(next_point: F, speed_factor: f32) -> impl Action<S>
 where
-    F: FnMut(&mut NpcCtx) -> Option<Vec2<f32>> + Send + Sync + 'static,
+    F: FnMut(&mut NpcCtx) -> Option<Vec2<f32>> + Clone + Send + Sync + 'static,
 {
-    until(move |ctx| {
+    until(move |ctx, next_point: &mut F| {
         let wpos = next_point(ctx)?;
 
         let wpos_site = |wpos: Vec2<f32>| {
@@ -437,11 +462,12 @@ where
             Some(Either::Right(goto_2d(wpos, speed_factor, 8.0)))
         }
     })
+    .with_state(next_point)
 }
 
 /// Try to travel to a site. Where practical, paths will be taken.
-fn travel_to_point(wpos: Vec2<f32>, speed_factor: f32) -> impl Action {
-    now(move |ctx| {
+fn travel_to_point<S: State>(wpos: Vec2<f32>, speed_factor: f32) -> impl Action<S> {
+    now(move |ctx, _| {
         const WAYPOINT: f32 = 48.0;
         let start = ctx.npc.wpos.xy();
         let diff = wpos - start;
@@ -453,8 +479,8 @@ fn travel_to_point(wpos: Vec2<f32>, speed_factor: f32) -> impl Action {
 }
 
 /// Try to travel to a site. Where practical, paths will be taken.
-fn travel_to_site(tgt_site: SiteId, speed_factor: f32) -> impl Action {
-    now(move |ctx| {
+fn travel_to_site<S: State>(tgt_site: SiteId, speed_factor: f32) -> impl Action<S> {
+    now(move |ctx, _| {
         let sites = &ctx.state.data().sites;
 
         let site_wpos = sites.get(tgt_site).map(|site| site.wpos.as_());
@@ -540,20 +566,14 @@ fn travel_to_site(tgt_site: SiteId, speed_factor: f32) -> impl Action {
             finish().boxed()
         }
             // Stop the NPC early if we're near the site to prevent huddling around the centre
-            .stop_if(move |ctx| site_wpos.map_or(false, |site_wpos| ctx.npc.wpos.xy().distance_squared(site_wpos) < 16f32.powi(2)))
+            .stop_if(move |ctx: &mut NpcCtx| site_wpos.map_or(false, |site_wpos| ctx.npc.wpos.xy().distance_squared(site_wpos) < 16f32.powi(2)))
     })
         .debug(move || format!("travel_to_site {:?}", tgt_site))
-        .map(|_| ())
+        .map(|_, _| ())
 }
 
-// Seconds
-fn timeout(time: f64) -> impl FnMut(&mut NpcCtx) -> bool + Clone + Send + Sync {
-    let mut timeout = None;
-    move |ctx| ctx.time.0 > *timeout.get_or_insert(ctx.time.0 + time)
-}
-
-fn talk_to(tgt: Actor, _subject: Option<Subject>) -> impl Action {
-    now(move |ctx| {
+fn talk_to<S: State>(tgt: Actor, _subject: Option<Subject>) -> impl Action<S> {
+    now(move |ctx, _| {
         if matches!(tgt, Actor::Npc(_)) && ctx.rng.gen_bool(0.2) {
             // Cut off the conversation sometimes to avoid infinite conversations (but only
             // if the target is an NPC!) TODO: Don't special case this, have
@@ -598,23 +618,23 @@ fn talk_to(tgt: Actor, _subject: Option<Subject>) -> impl Action {
             idle()
                 .repeat()
                 .stop_if(timeout(wait))
-                .then(just(move |ctx| ctx.controller.say(tgt, comment.clone())))
+                .then(just(move |ctx, _| ctx.controller.say(tgt, comment.clone())))
                 .r()
         }
     })
 }
 
-fn socialize() -> impl Action {
-    now(|ctx| {
+fn socialize() -> impl Action<EveryRange> {
+    now(move |ctx, socialize: &mut EveryRange| {
         // Skip most socialising actions if we're not loaded
-        if matches!(ctx.npc.mode, SimulationMode::Loaded) && ctx.rng.gen_bool(0.002) {
+        if matches!(ctx.npc.mode, SimulationMode::Loaded) && socialize.should(ctx) {
             // Sometimes dance
             if ctx.rng.gen_bool(0.15) {
-                return just(|ctx| ctx.controller.do_dance())
+                return just(|ctx, _| ctx.controller.do_dance())
                     .repeat()
                     .stop_if(timeout(6.0))
                     .debug(|| "dancing")
-                    .map(|_| ())
+                    .map(|_, _| ())
                     .l()
                     .l();
             // Talk to nearby NPCs
@@ -628,17 +648,16 @@ fn socialize() -> impl Action {
                 return talk_to(other, None)
                     // After talking, wait for a while
                     .then(idle().repeat().stop_if(timeout(4.0)))
-                    .map(|_| ())
+                    .map(|_, _| ())
                     .r().l();
             }
         }
-
         idle().r()
     })
 }
 
-fn adventure() -> impl Action {
-    choose(|ctx| {
+fn adventure() -> impl Action<DefaultState> {
+    choose(|ctx, _| {
         // Choose a random site that's fairly close by
         if let Some(tgt_site) = ctx
             .state
@@ -670,11 +689,11 @@ fn adventure() -> impl Action {
                 .map(|ws| ctx.index.sites.get(ws).name().to_string())
                 .unwrap_or_default();
             // Travel to the site
-            important(just(move |ctx| ctx.controller.say(None, Content::localized_with_args("npc-speech-moving_on", [("site", site_name.clone())])))
+            important(just(move |ctx, _| ctx.controller.say(None, Content::localized_with_args("npc-speech-moving_on", [("site", site_name.clone())])))
                 .then(travel_to_site(tgt_site, 0.6))
                 // Stop for a few minutes
                 .then(villager(tgt_site).repeat().stop_if(timeout(wait_time)))
-                .map(|_| ())
+                .map(|_, _| ())
                 .boxed(),
             )
         } else {
@@ -684,8 +703,8 @@ fn adventure() -> impl Action {
     .debug(move || "adventure")
 }
 
-fn gather_ingredients() -> impl Action {
-    just(|ctx| {
+fn gather_ingredients<S: State>() -> impl Action<S> {
+    just(|ctx, _| {
         ctx.controller.do_gather(
             &[
                 ChunkResource::Fruit,
@@ -697,8 +716,8 @@ fn gather_ingredients() -> impl Action {
     .debug(|| "gather ingredients")
 }
 
-fn hunt_animals() -> impl Action {
-    just(|ctx| ctx.controller.do_hunt_animals()).debug(|| "hunt_animals")
+fn hunt_animals<S: State>() -> impl Action<S> {
+    just(|ctx, _| ctx.controller.do_hunt_animals()).debug(|| "hunt_animals")
 }
 
 fn find_forest(ctx: &mut NpcCtx) -> Option<Vec2<f32>> {
@@ -732,10 +751,10 @@ fn choose_plaza(ctx: &mut NpcCtx, site: SiteId) -> Option<Vec2<f32>> {
         })
 }
 
-fn villager(visiting_site: SiteId) -> impl Action {
-    choose(move |ctx| {
+fn villager(visiting_site: SiteId) -> impl Action<DefaultState> {
+    choose(move |ctx, state: &mut DefaultState| {
         // Consider moving home if the home site gets too full
-        if ctx.rng.gen_bool(0.0001)
+        if state.move_home_timer.should(ctx)
             && let Some(home) = ctx.npc.home
             && Some(home) == ctx.npc.current_site
             && let Some(home_pop_ratio) = ctx.state.data().sites.get(home)
@@ -769,20 +788,20 @@ fn villager(visiting_site: SiteId) -> impl Action {
         {
             let site_name = ctx.state.data().sites[new_home].world_site
                 .map(|ws| ctx.index.sites.get(ws).name().to_string());
-            return important(just(move |ctx| {
+            return important(just(move |ctx, _| {
                 if let Some(site_name) = &site_name {
                     ctx.controller.say(None, Content::localized_with_args("npc-speech-migrating", [("site", site_name.clone())]))
                 }
             })
                 .then(travel_to_site(new_home, 0.5))
-                .then(just(move |ctx| ctx.controller.set_new_home(new_home))));
+                .then(just(move |ctx, _| ctx.controller.set_new_home(new_home))));
         }
 
         if DayPeriod::from(ctx.time_of_day.0).is_dark()
             && !matches!(ctx.npc.profession(), Some(Profession::Guard))
         {
             return important(
-                now(move |ctx| {
+                now(move |ctx, _| {
                     if let Some(house_wpos) = ctx
                         .state
                         .data()
@@ -798,19 +817,19 @@ fn villager(visiting_site: SiteId) -> impl Action {
                             Some(site2.tile_center_wpos(house.root_tile()).as_())
                         })
                     {
-                        just(|ctx| {
+                        just(|ctx, _| {
                             ctx.controller
                                 .say(None, Content::localized("npc-speech-night_time"))
                         })
                         .then(travel_to_point(house_wpos, 0.65))
                         .debug(|| "walk to house")
-                        .then(socialize().repeat().debug(|| "wait in house"))
-                        .stop_if(|ctx| DayPeriod::from(ctx.time_of_day.0).is_light())
-                        .then(just(|ctx| {
+                        .then(socialize().repeat().map_state(|state: &mut DefaultState| &mut state.socialize_timer).debug(|| "wait in house"))
+                        .stop_if(|ctx: &mut NpcCtx| DayPeriod::from(ctx.time_of_day.0).is_light())
+                        .then(just(|ctx, _| {
                             ctx.controller
                                 .say(None, Content::localized("npc-speech-day_time"))
                         }))
-                        .map(|_| ())
+                        .map(|_, _| ())
                         .boxed()
                     } else {
                         finish().boxed()
@@ -829,13 +848,13 @@ fn villager(visiting_site: SiteId) -> impl Action {
                             let wait_time = ctx.rng.gen_range(10.0..30.0);
                             gather_ingredients().repeat().stop_if(timeout(wait_time))
                         })
-                        .map(|_| ()),
+                        .map(|_, _| ()),
                 );
             }
         } else if matches!(ctx.npc.profession(), Some(Profession::Hunter)) && ctx.rng.gen_bool(0.8) {
             if let Some(forest_wpos) = find_forest(ctx) {
                 return casual(
-                    just(|ctx| {
+                    just(|ctx, _| {
                         ctx.controller
                             .say(None, Content::localized("npc-speech-start_hunting"))
                     })
@@ -845,7 +864,7 @@ fn villager(visiting_site: SiteId) -> impl Action {
                         let wait_time = ctx.rng.gen_range(30.0..60.0);
                         hunt_animals().repeat().stop_if(timeout(wait_time))
                     })
-                    .map(|_| ()),
+                    .map(|_, _| ()),
                 );
             }
         } else if matches!(ctx.npc.profession(), Some(Profession::Guard)) && ctx.rng.gen_bool(0.7) {
@@ -853,9 +872,9 @@ fn villager(visiting_site: SiteId) -> impl Action {
                 return casual(
                     travel_to_point(plaza_wpos, 0.4)
                         .debug(|| "patrol")
-                        .interrupt_with(|ctx| {
+                        .interrupt_with(move |ctx, _| {
                             if ctx.rng.gen_bool(0.0003) {
-                                Some(just(move |ctx| {
+                                Some(just(move |ctx, _| {
                                     ctx.controller
                                         .say(None, Content::localized("npc-speech-guard_thought"))
                                 }))
@@ -863,13 +882,13 @@ fn villager(visiting_site: SiteId) -> impl Action {
                                 None
                             }
                         })
-                        .map(|_| ()),
+                        .map(|_, _| ()),
                 );
             }
         } else if matches!(ctx.npc.profession(), Some(Profession::Merchant)) && ctx.rng.gen_bool(0.8)
         {
             return casual(
-                just(|ctx| {
+                just(|ctx, _| {
                     // Try to direct our speech at nearby actors, if there are any
                     let (target, phrase) = if ctx.rng.gen_bool(0.3) && let Some(other) = ctx
                         .state
@@ -890,12 +909,12 @@ fn villager(visiting_site: SiteId) -> impl Action {
                 .repeat()
                 .stop_if(timeout(60.0))
                 .debug(|| "sell wares")
-                .map(|_| ()),
+                .map(|_, _| ()),
             );
         }
 
         // If nothing else needs doing, walk between plazas and socialize
-        casual(now(move |ctx| {
+        casual(now(move |ctx, _| {
             // Choose a plaza in the site we're visiting to walk to
             if let Some(plaza_wpos) = choose_plaza(ctx, visiting_site) {
                 // Walk to the plaza...
@@ -908,9 +927,10 @@ fn villager(visiting_site: SiteId) -> impl Action {
                 // ...then socialize for some time before moving on
                 .then(socialize()
                     .repeat()
+                    .map_state(|state: &mut DefaultState| &mut state.socialize_timer)
                     .stop_if(timeout(ctx.rng.gen_range(30.0..90.0)))
                     .debug(|| "wait at plaza"))
-                .map(|_| ())
+                .map(|_, _| ())
         }))
     })
     .debug(move || format!("villager at site {:?}", visiting_site))
@@ -937,9 +957,9 @@ fn follow(npc: NpcId, distance: f32) -> impl Action {
 }
 */
 
-fn pilot(ship: common::comp::ship::Body) -> impl Action {
+fn pilot<S: State>(ship: common::comp::ship::Body) -> impl Action<S> {
     // Travel between different towns in a straight line
-    now(move |ctx| {
+    now(move |ctx, _| {
         let data = &*ctx.state.data();
         let site = data
             .sites
@@ -968,12 +988,12 @@ fn pilot(ship: common::comp::ship::Body) -> impl Action {
         }
     })
     .repeat()
-    .map(|_| ())
+    .map(|_, _| ())
 }
 
-fn captain() -> impl Action {
+fn captain<S: State>() -> impl Action<S> {
     // For now just randomly travel the sea
-    now(|ctx| {
+    now(|ctx, _| {
         let chunk = ctx.npc.wpos.xy().as_().wpos_to_cpos();
         if let Some(chunk) = NEIGHBORS
             .into_iter()
@@ -999,10 +1019,10 @@ fn captain() -> impl Action {
         }
     })
     .repeat()
-    .map(|_| ())
+    .map(|_, _| ())
 }
 
-fn check_inbox(ctx: &mut NpcCtx) -> Option<impl Action> {
+fn check_inbox<S: State>(ctx: &mut NpcCtx) -> Option<impl Action<S>> {
     loop {
         match ctx.inbox.pop_front() {
             Some(NpcInput::Report(report_id)) if !ctx.known_reports.contains(&report_id) => {
@@ -1047,8 +1067,10 @@ fn check_inbox(ctx: &mut NpcCtx) -> Option<impl Action> {
                         };
                         ctx.known_reports.insert(report_id);
                         break Some(
-                            just(move |ctx| ctx.controller.say(killer, Content::localized(phrase)))
-                                .l(),
+                            just(move |ctx, _| {
+                                ctx.controller.say(killer, Content::localized(phrase))
+                            })
+                            .l(),
                         );
                     },
                     Some(ReportKind::Death { .. }) => {}, // We don't care about death
@@ -1062,7 +1084,7 @@ fn check_inbox(ctx: &mut NpcCtx) -> Option<impl Action> {
     }
 }
 
-fn check_for_enemies(ctx: &mut NpcCtx) -> Option<impl Action> {
+fn check_for_enemies<S: State>(ctx: &mut NpcCtx) -> Option<impl Action<S>> {
     // TODO: Instead of checking all nearby actors every tick, it would be more
     // effective to have the actor grid generate a per-tick diff so that we only
     // need to check new actors in the local area. Be careful though:
@@ -1074,17 +1096,17 @@ fn check_for_enemies(ctx: &mut NpcCtx) -> Option<impl Action> {
         .npcs
         .nearby(Some(ctx.npc_id), ctx.npc.wpos, 24.0)
         .find(|actor| ctx.sentiments.toward(*actor).is(Sentiment::ENEMY))
-        .map(|enemy| just(move |ctx| ctx.controller.attack(enemy)))
+        .map(|enemy| just(move |ctx, _| ctx.controller.attack(enemy)))
 }
 
-fn react_to_events(ctx: &mut NpcCtx) -> Option<impl Action> {
-    check_inbox(ctx)
+fn react_to_events<S: State>(ctx: &mut NpcCtx, _: &mut S) -> Option<impl Action<S>> {
+    check_inbox::<S>(ctx)
         .map(|action| action.boxed())
         .or_else(|| check_for_enemies(ctx).map(|action| action.boxed()))
 }
 
-fn humanoid() -> impl Action {
-    choose(|ctx| {
+fn humanoid() -> impl Action<DefaultState> {
+    choose(|ctx, _| {
         if let Some(riding) = &ctx.npc.riding {
             if riding.steering {
                 if let Some(vehicle) = ctx.state.data().npcs.vehicles.get(riding.vehicle) {
@@ -1100,7 +1122,9 @@ fn humanoid() -> impl Action {
                     casual(finish())
                 }
             } else {
-                important(socialize())
+                important(
+                    socialize().map_state(|state: &mut DefaultState| &mut state.socialize_timer),
+                )
             }
         } else {
             let action = if matches!(
@@ -1119,8 +1143,8 @@ fn humanoid() -> impl Action {
     })
 }
 
-fn bird_large() -> impl Action {
-    choose(|ctx| {
+fn bird_large() -> impl Action<DefaultState> {
+    choose(|ctx, _| {
         let data = ctx.state.data();
         if let Some(home) = ctx.npc.home {
             let is_home = ctx.npc.current_site.map_or(false, |site| home == site);
@@ -1161,26 +1185,58 @@ fn bird_large() -> impl Action {
     })
 }
 
-fn monster() -> impl Action {
-    let mut bearing = Vec2::zero();
-    now(move |ctx| {
-        bearing = bearing
+fn monster() -> impl Action<DefaultState> {
+    now(|ctx, bearing: &mut Vec2<f32>| {
+        *bearing = bearing
             .map(|e| e + ctx.rng.gen_range(-0.1..0.1))
             .try_normalized()
             .unwrap_or_default();
-        goto_2d(ctx.npc.wpos.xy() + bearing * 24.0, 0.7, 8.0)
-            .debug(move || format!("Moving with a bearing of {:?}", bearing))
+        let bearing_dist = 24.0;
+        let mut pos = ctx.npc.wpos.xy() + *bearing * bearing_dist;
+        let is_deep_water = ctx
+            .world
+            .sim()
+            .get_interpolated(pos.as_(), |c| c.alt - c.water_alt)
+            .unwrap_or(f32::NEG_INFINITY)
+            < -10.0
+            && ctx
+                .world
+                .sim()
+                .get(pos.as_().wpos_to_cpos())
+                .map_or(false, |c| c.river.is_ocean() || c.river.is_lake());
+        if !is_deep_water {
+            goto_2d(pos, 0.7, 8.0)
+        } else {
+            *bearing *= -1.0;
+
+            pos = ctx.npc.wpos.xy() + *bearing * 24.0;
+
+            goto_2d(pos, 0.7, 8.0)
+        }
+        // If we are too far away from our goal position we can stop since we aren't going to a specific place.
+        .stop_if(move |ctx: &mut NpcCtx| {
+            ctx.npc.wpos.xy().distance_squared(pos) > (bearing_dist + 5.0).powi(2)
+        })
+        .debug({
+            let bearing = *bearing;
+            move || format!("Moving with a bearing of {:?}", bearing)
+        })
     })
     .repeat()
-    .map(|_| ())
+    .with_state(Vec2::<f32>::zero())
+    .map(|_, _| ())
 }
 
-fn think() -> impl Action {
-    now(|ctx| match ctx.npc.body {
+fn think() -> impl Action<DefaultState> {
+    now(|ctx, _| match ctx.npc.body {
         common::comp::Body::Humanoid(_) => humanoid().l().l().l(),
         common::comp::Body::BirdLarge(_) => bird_large().r().l().l(),
         _ => match &ctx.npc.role {
-            Role::Civilised(_) => socialize().l().r().l(),
+            Role::Civilised(_) => socialize()
+                .map_state(|state: &mut DefaultState| &mut state.socialize_timer)
+                .l()
+                .r()
+                .l(),
             Role::Monster => monster().r().r().l(),
             Role::Wild => idle().r(),
         },
diff --git a/rtsim/src/rule/simulate_npcs.rs b/rtsim/src/rule/simulate_npcs.rs
index 82cf095394..39a94056f6 100644
--- a/rtsim/src/rule/simulate_npcs.rs
+++ b/rtsim/src/rule/simulate_npcs.rs
@@ -1,26 +1,29 @@
 use crate::{
     data::{npc::SimulationMode, Npc},
-    event::{EventCtx, OnDeath, OnSetup, OnTick},
+    event::{EventCtx, OnDeath, OnMountVolume, OnSetup, OnTick},
     RtState, Rule, RuleError,
 };
 use common::{
     comp::{self, Body},
+    mounting::{Volume, VolumePos},
     rtsim::{Actor, NpcAction, NpcActivity, Personality},
-    terrain::CoordinateConversions,
+    terrain::{CoordinateConversions, TerrainChunkSize},
+    vol::RectVolSize,
 };
 use rand::prelude::*;
 use rand_chacha::ChaChaRng;
 use tracing::{error, warn};
-use vek::Vec2;
+use vek::{Clamp, Vec2};
 use world::site::SiteKind;
 
 pub struct SimulateNpcs;
 
 impl Rule for SimulateNpcs {
     fn start(rtstate: &mut RtState) -> Result<Self, RuleError> {
-        rtstate.bind::<Self, OnSetup>(on_setup);
-        rtstate.bind::<Self, OnDeath>(on_death);
-        rtstate.bind::<Self, OnTick>(on_tick);
+        rtstate.bind(on_setup);
+        rtstate.bind(on_death);
+        rtstate.bind(on_tick);
+        rtstate.bind(on_mount_volume);
 
         Ok(Self)
     }
@@ -43,6 +46,17 @@ fn on_setup(ctx: EventCtx<SimulateNpcs, OnSetup>) {
     }
 }
 
+fn on_mount_volume(ctx: EventCtx<SimulateNpcs, OnMountVolume>) {
+    let data = &mut *ctx.state.data_mut();
+
+    if let VolumePos { kind: Volume::Entity(vehicle), .. } = ctx.event.pos
+        && let Some(vehicle) = data.npcs.vehicles.get(vehicle)
+        && let Some(Actor::Npc(driver)) = vehicle.driver
+        && let Some(driver) = data.npcs.get_mut(driver)  {
+        driver.controller.actions.push(NpcAction::Say(Some(ctx.event.actor), comp::Content::localized("npc-speech-welcome-aboard")))
+    }
+}
+
 fn on_death(ctx: EventCtx<SimulateNpcs, OnDeath>) {
     let data = &mut *ctx.state.data_mut();
 
@@ -238,6 +252,20 @@ fn on_tick(ctx: EventCtx<SimulateNpcs, OnTick>) {
                     },
                     None => {},
                 }
+                // Make sure NPCs remain on the surface and within the map
+                npc.wpos = npc
+                    .wpos
+                    .xy()
+                    .clamped(
+                        Vec2::zero(),
+                        (ctx.world.sim().get_size() * TerrainChunkSize::RECT_SIZE).as_(),
+                    )
+                    .with_z(
+                        ctx.world
+                            .sim()
+                            .get_surface_alt_approx(npc.wpos.xy().map(|e| e as i32))
+                            + npc.body.flying_height(),
+                    );
             }
 
             // Consume NPC actions
@@ -247,13 +275,6 @@ fn on_tick(ctx: EventCtx<SimulateNpcs, OnTick>) {
                     NpcAction::Attack(_) => {}, // TODO: Implement simulated combat
                 }
             }
-            // Make sure NPCs remain on the surface
-            npc.wpos.z = ctx
-                .world
-                .sim()
-                .get_surface_alt_approx(npc.wpos.xy().map(|e| e as i32))
-                .unwrap_or(0.0)
-                + npc.body.flying_height();
         }
 
         // Move home if required
@@ -271,4 +292,24 @@ fn on_tick(ctx: EventCtx<SimulateNpcs, OnTick>) {
             npc.home = Some(new_home);
         }
     }
+
+    for (_, vehicle) in data.npcs.vehicles.iter_mut() {
+        // Try to keep ships above ground and within the map
+        if matches!(vehicle.mode, SimulationMode::Simulated) {
+            vehicle.wpos = vehicle
+                .wpos
+                .xy()
+                .clamped(
+                    Vec2::zero(),
+                    (ctx.world.sim().get_size() * TerrainChunkSize::RECT_SIZE).as_(),
+                )
+                .with_z(
+                    vehicle.wpos.z.max(
+                        ctx.world
+                            .sim()
+                            .get_surface_alt_approx(vehicle.wpos.xy().as_()),
+                    ),
+                );
+        }
+    }
 }
diff --git a/server/src/client.rs b/server/src/client.rs
index bd6ec33458..d2a76bf44a 100644
--- a/server/src/client.rs
+++ b/server/src/client.rs
@@ -203,7 +203,7 @@ impl Client {
                     | ServerGeneral::ChatMsg(_)
                     | ServerGeneral::ChatMode(_)
                     | ServerGeneral::SetPlayerEntity(_)
-                    | ServerGeneral::TimeOfDay(_, _, _)
+                    | ServerGeneral::TimeOfDay(_, _, _, _)
                     | ServerGeneral::EntitySync(_)
                     | ServerGeneral::CompSync(_, _)
                     | ServerGeneral::CreateEntity(_)
diff --git a/server/src/cmd.rs b/server/src/cmd.rs
index eecc4f06da..6d53e28c94 100644
--- a/server/src/cmd.rs
+++ b/server/src/cmd.rs
@@ -44,7 +44,7 @@ use common::{
     npc::{self, get_npc_name},
     outcome::Outcome,
     parse_cmd_args,
-    resources::{BattleMode, PlayerPhysicsSettings, Secs, Time, TimeOfDay},
+    resources::{BattleMode, PlayerPhysicsSettings, Secs, Time, TimeOfDay, TimeScale},
     rtsim::{Actor, Role},
     terrain::{Block, BlockKind, CoordinateConversions, SpriteKind, TerrainChunkSize},
     uid::{Uid, UidAllocator},
@@ -186,6 +186,7 @@ fn do_command(
         ServerChatCommand::Sudo => handle_sudo,
         ServerChatCommand::Tell => handle_tell,
         ServerChatCommand::Time => handle_time,
+        ServerChatCommand::TimeScale => handle_time_scale,
         ServerChatCommand::Tp => handle_tp,
         ServerChatCommand::RtsimTp => handle_rtsim_tp,
         ServerChatCommand::RtsimInfo => handle_rtsim_info,
@@ -1118,12 +1119,14 @@ fn handle_time(
     let mut tod_lazymsg = None;
     let clients = server.state.ecs().read_storage::<Client>();
     let calendar = server.state.ecs().read_resource::<Calendar>();
+    let time_scale = server.state.ecs().read_resource::<TimeScale>();
     for client in (&clients).join() {
         let msg = tod_lazymsg.unwrap_or_else(|| {
             client.prepare(ServerGeneral::TimeOfDay(
                 TimeOfDay(new_time),
                 (*calendar).clone(),
                 *time,
+                *time_scale,
             ))
         });
         let _ = client.send_prepared(&msg);
@@ -1144,6 +1147,64 @@ fn handle_time(
     Ok(())
 }
 
+fn handle_time_scale(
+    server: &mut Server,
+    client: EcsEntity,
+    _target: EcsEntity,
+    args: Vec<String>,
+    _action: &ServerChatCommand,
+) -> CmdResult<()> {
+    let time_scale = server
+        .state
+        .ecs_mut()
+        .get_mut::<TimeScale>()
+        .expect("Expected time scale to be added.");
+    if args.is_empty() {
+        let time_scale = time_scale.0;
+        server.notify_client(
+            client,
+            ServerGeneral::server_msg(
+                ChatType::CommandInfo,
+                format!("The current time scale is {time_scale}."),
+            ),
+        );
+    } else if let Some(scale) = parse_cmd_args!(args, f64) {
+        time_scale.0 = scale.clamp(0.0001, 1000.0);
+        server.notify_client(
+            client,
+            ServerGeneral::server_msg(ChatType::CommandInfo, format!("Set time scale to {scale}.")),
+        );
+        // Update all clients with the new TimeOfDay (without this they would have to
+        // wait for the next 100th tick to receive the update).
+        let mut tod_lazymsg = None;
+        let clients = server.state.ecs().read_storage::<Client>();
+        let time = server.state.ecs().read_resource::<Time>();
+        let time_of_day = server.state.ecs().read_resource::<TimeOfDay>();
+        let calendar = server.state.ecs().read_resource::<Calendar>();
+        for client in (&clients).join() {
+            let msg = tod_lazymsg.unwrap_or_else(|| {
+                client.prepare(ServerGeneral::TimeOfDay(
+                    *time_of_day,
+                    (*calendar).clone(),
+                    *time,
+                    TimeScale(scale),
+                ))
+            });
+            let _ = client.send_prepared(&msg);
+            tod_lazymsg = Some(msg);
+        }
+    } else {
+        server.notify_client(
+            client,
+            ServerGeneral::server_msg(
+                ChatType::CommandError,
+                "Wrong parameter, expected f32.".to_string(),
+            ),
+        );
+    }
+    Ok(())
+}
+
 fn handle_health(
     server: &mut Server,
     _client: EcsEntity,
@@ -1302,6 +1363,7 @@ fn handle_rtsim_info(
 
         let _ = writeln!(&mut info, "-- General Information --");
         let _ = writeln!(&mut info, "Seed: {}", npc.seed);
+        let _ = writeln!(&mut info, "Pos: {:?}", npc.wpos);
         let _ = writeln!(&mut info, "Role: {:?}", npc.role);
         let _ = writeln!(&mut info, "Home: {:?}", npc.home);
         let _ = writeln!(&mut info, "Faction: {:?}", npc.faction);
@@ -1309,6 +1371,11 @@ fn handle_rtsim_info(
         let _ = writeln!(&mut info, "-- Status --");
         let _ = writeln!(&mut info, "Current site: {:?}", npc.current_site);
         let _ = writeln!(&mut info, "Current mode: {:?}", npc.mode);
+        let _ = writeln!(
+            &mut info,
+            "Riding: {:?}",
+            npc.riding.as_ref().map(|riding| riding.vehicle)
+        );
         let _ = writeln!(&mut info, "-- Action State --");
         if let Some(brain) = &npc.brain {
             let mut bt = Vec::new();
@@ -1345,7 +1412,7 @@ fn handle_rtsim_npc(
             .filter(|s| !s.is_empty())
             .map(|s| s.trim().to_lowercase())
             .collect::<Vec<_>>();
-
+        let npc_names = &*common::npc::NPC_NAMES.read();
         let rtsim = server.state.ecs().read_resource::<RtSim>();
         let data = rtsim.state().data();
         let mut npcs = data
@@ -1353,7 +1420,7 @@ fn handle_rtsim_npc(
             .values()
             .enumerate()
             .filter(|(idx, npc)| {
-                let tags = [
+                let mut tags = vec![
                     npc.profession()
                         .map(|p| format!("{:?}", p))
                         .unwrap_or_default(),
@@ -1364,7 +1431,11 @@ fn handle_rtsim_npc(
                     },
                     format!("{:?}", npc.mode),
                     format!("{}", idx),
+                    npc_names[&npc.body].keyword.clone(),
                 ];
+                if let Some(species_meta) = npc_names.get_species_meta(&npc.body) {
+                    tags.push(species_meta.keyword.clone());
+                }
                 terms
                     .iter()
                     .all(|term| tags.iter().any(|tag| term.eq_ignore_ascii_case(tag.trim())))
diff --git a/server/src/events/interaction.rs b/server/src/events/interaction.rs
index b0e3a57b81..009b5692ce 100644
--- a/server/src/events/interaction.rs
+++ b/server/src/events/interaction.rs
@@ -1,4 +1,4 @@
-use specs::{world::WorldExt, Entity as EcsEntity, Join};
+use specs::{saveload::MarkerAllocator, world::WorldExt, Entity as EcsEntity, Join};
 use vek::*;
 
 use common::{
@@ -19,19 +19,20 @@ use common::{
     link::Is,
     mounting::{Mounting, Rider, VolumeMounting, VolumePos, VolumeRider},
     outcome::Outcome,
+    rtsim::RtSimVehicle,
     terrain::{Block, SpriteKind},
-    uid::Uid,
+    uid::{Uid, UidAllocator},
     vol::ReadVol,
 };
 use common_net::sync::WorldSyncExt;
 
-use crate::{state_ext::StateExt, Server, Time};
+use crate::{rtsim::RtSim, state_ext::StateExt, Server, Time};
 
 use crate::pet::tame_pet;
 use hashbrown::{HashMap, HashSet};
 use lazy_static::lazy_static;
 use serde::Deserialize;
-use std::iter::FromIterator;
+use std::{iter::FromIterator, sync::Arc};
 
 pub fn handle_lantern(server: &mut Server, entity: EcsEntity, enable: bool) {
     let ecs = server.state_mut().ecs();
@@ -169,11 +170,28 @@ pub fn handle_mount_volume(server: &mut Server, rider: EcsEntity, volume_pos: Vo
         let maybe_uid = state.ecs().read_storage::<Uid>().get(rider).copied();
 
         if let Some(rider) = maybe_uid && within_range {
-            let _ = state.link(VolumeMounting {
+            let _link_successful = state.link(VolumeMounting {
                 pos: volume_pos,
                 block,
                 rider,
-            });
+            }).is_ok();
+            #[cfg(feature = "worldgen")] 
+            if _link_successful {
+                let uid_allocator = state.ecs().read_resource::<UidAllocator>();
+                if let Some(rider_entity) = uid_allocator.retrieve_entity_internal(rider.0)
+                    && let Some(rider_actor) = state.entity_as_actor(rider_entity)
+                    && let Some(volume_pos) = volume_pos.try_map_entity(|uid| {
+                        let entity = uid_allocator.retrieve_entity_internal(uid.0)?;
+                        state.read_storage::<RtSimVehicle>().get(entity).map(|v| v.0)
+                    }) {
+                    state.ecs().write_resource::<RtSim>().hook_character_mount_volume(
+                            &state.ecs().read_resource::<Arc<world::World>>(),
+                            state.ecs().read_resource::<world::IndexOwned>().as_index_ref(),
+                            volume_pos,
+                            rider_actor,
+                    );
+                }
+            }
         }
     }
 }
diff --git a/server/src/rtsim/mod.rs b/server/src/rtsim/mod.rs
index 2f07882f26..50634d09fe 100644
--- a/server/src/rtsim/mod.rs
+++ b/server/src/rtsim/mod.rs
@@ -5,7 +5,8 @@ pub mod tick;
 use atomicwrites::{AtomicFile, OverwriteBehavior};
 use common::{
     grid::Grid,
-    rtsim::{Actor, ChunkResource, RtSimEntity, RtSimVehicle, WorldSettings},
+    mounting::VolumePos,
+    rtsim::{Actor, ChunkResource, RtSimEntity, RtSimVehicle, VehicleId, WorldSettings},
 };
 use common_ecs::dispatch;
 use common_state::BlockDiff;
@@ -13,7 +14,7 @@ use crossbeam_channel::{unbounded, Receiver, Sender};
 use enum_map::EnumMap;
 use rtsim::{
     data::{npc::SimulationMode, Data, ReadError},
-    event::{OnDeath, OnSetup},
+    event::{OnDeath, OnMountVolume, OnSetup},
     RtState,
 };
 use specs::DispatcherBuilder;
@@ -147,6 +148,16 @@ impl RtSim {
         path
     }
 
+    pub fn hook_character_mount_volume(
+        &mut self,
+        world: &World,
+        index: IndexRef,
+        pos: VolumePos<VehicleId>,
+        actor: Actor,
+    ) {
+        self.state.emit(OnMountVolume { actor, pos }, world, index)
+    }
+
     pub fn hook_load_chunk(&mut self, key: Vec2<i32>, max_res: EnumMap<ChunkResource, usize>) {
         if let Some(chunk_state) = self.state.get_resource_mut::<ChunkStates>().0.get_mut(key) {
             *chunk_state = Some(LoadedChunkState { max_res });
@@ -167,14 +178,26 @@ impl RtSim {
     }
 
     pub fn hook_rtsim_entity_unload(&mut self, entity: RtSimEntity) {
-        if let Some(npc) = self.state.get_data_mut().npcs.get_mut(entity.0) {
+        if let Some(npc) = self
+            .state
+            .get_data_mut()
+            .npcs
+            .get_mut(entity.0)
+            .filter(|npc| npc.riding.is_none())
+        {
             npc.mode = SimulationMode::Simulated;
         }
     }
 
     pub fn hook_rtsim_vehicle_unload(&mut self, entity: RtSimVehicle) {
-        if let Some(vehicle) = self.state.get_data_mut().npcs.vehicles.get_mut(entity.0) {
+        let data = self.state.get_data_mut();
+        if let Some(vehicle) = data.npcs.vehicles.get_mut(entity.0) {
             vehicle.mode = SimulationMode::Simulated;
+            if let Some(Actor::Npc(npc)) = vehicle.driver {
+                if let Some(npc) = data.npcs.get_mut(npc) {
+                    npc.mode = SimulationMode::Simulated;
+                }
+            }
         }
     }
 
diff --git a/server/src/sys/entity_sync.rs b/server/src/sys/entity_sync.rs
index 0dc785aa0a..b73b18690f 100644
--- a/server/src/sys/entity_sync.rs
+++ b/server/src/sys/entity_sync.rs
@@ -6,7 +6,7 @@ use common::{
     event::EventBus,
     outcome::Outcome,
     region::{Event as RegionEvent, RegionMap},
-    resources::{PlayerPhysicsSettings, Time, TimeOfDay},
+    resources::{PlayerPhysicsSettings, Time, TimeOfDay, TimeScale},
     terrain::TerrainChunkSize,
     uid::Uid,
     vol::RectVolSize,
@@ -31,6 +31,7 @@ impl<'a> System<'a> for Sys {
         ReadExpect<'a, TimeOfDay>,
         ReadExpect<'a, Time>,
         ReadExpect<'a, Calendar>,
+        ReadExpect<'a, TimeScale>,
         ReadExpect<'a, RegionMap>,
         ReadExpect<'a, UpdateTrackers>,
         ReadStorage<'a, Pos>,
@@ -63,6 +64,7 @@ impl<'a> System<'a> for Sys {
             time_of_day,
             time,
             calendar,
+            time_scale,
             region_map,
             trackers,
             positions,
@@ -418,6 +420,7 @@ impl<'a> System<'a> for Sys {
                         *time_of_day,
                         (*calendar).clone(),
                         *time,
+                        *time_scale,
                     ))
                 });
                 // We don't care much about stream errors here since they could just represent
diff --git a/world/src/sim/mod.rs b/world/src/sim/mod.rs
index aa4797abe1..c9d140f28c 100644
--- a/world/src/sim/mod.rs
+++ b/world/src/sim/mod.rs
@@ -1931,10 +1931,11 @@ impl WorldSim {
     }
 
     /// Get the altitude of the surface, could be water or ground.
-    pub fn get_surface_alt_approx(&self, wpos: Vec2<i32>) -> Option<f32> {
+    pub fn get_surface_alt_approx(&self, wpos: Vec2<i32>) -> f32 {
         self.get_interpolated(wpos, |chunk| chunk.alt)
             .zip(self.get_interpolated(wpos, |chunk| chunk.water_alt))
             .map(|(alt, water_alt)| alt.max(water_alt))
+            .unwrap_or(CONFIG.sea_level)
     }
 
     pub fn get_alt_approx(&self, wpos: Vec2<i32>) -> Option<f32> {
diff --git a/world/src/site2/plot/bridge.rs b/world/src/site2/plot/bridge.rs
index fb4ab87735..44bda8eac1 100644
--- a/world/src/site2/plot/bridge.rs
+++ b/world/src/site2/plot/bridge.rs
@@ -258,7 +258,7 @@ fn render_flat(bridge: &Bridge, painter: &Painter) {
 
     let len = bridge.dir.select(aabr.size());
     let true_offset = vault_width + vault_offset;
-    let n = len / true_offset;
+    let n = (len / true_offset).max(1);
     let p = len / n;
 
     let holes = painter