feat: slime enemies — jump AI, contact damage, combat system

New entity: Slime (EntityKind::Slime)
- 19 parts: blobby body (3x5) + 2 glowing eyes
- Green translucent colors, brighter center
- HP: 25, spawns every 45 ticks (max 2 alive)

Slime AI (update_slime_ai):
- Jumps toward player every 60 ticks when within 40 cells
- Jump power scales with proximity (closer = stronger)
- Pauses horizontally between jumps (50/50 hop-stop cycle)
- Uses set_horizontal_vel + set_vertical_vel (vector movement)

Combat system (update_combat):
- AABB overlap check between player and all alive enemies
- Goblin: 8 damage per 20 ticks on contact
- Slime: 5 damage per 20 ticks on contact
- Knockback: player pushed away from enemy on hit
- Player.take_damage() called, death possible from enemies

World gen: try_spawn_slime() spawns at surface, 18 cells from player
Renderers: slime rendered as 's' in ascii/terminal, green blob in graphics

6 new tests (122 total, 0 failures)

src/ai/state.rs

@@ -1,9 +1,9 @@
-use serde::{Deserialize, Serialize};
-use crate::entity::{EntityManager, EntityKind};
-use crate::world::grid::Grid;
-use crate::world::cell::MaterialId;
-use crate::world::material::MaterialRegistry;
+use crate::entity::{EntityKind, EntityManager};
 use crate::game::Game;
+use crate::world::cell::MaterialId;
+use crate::world::grid::Grid;
+use crate::world::material::MaterialRegistry;
+use serde::{Deserialize, Serialize};
 
 #[derive(Serialize, Deserialize, Clone, Debug)]
 pub struct GameState {
@@ -54,7 +54,8 @@ impl CellInfo {
     pub fn from_grid(grid: &Grid, x: i32, y: i32) -> Self {
         if !grid.in_bounds(x, y) {
             return Self {
-                x, y,
+                x,
+                y,
                 material: "out_of_bounds".to_string(),
                 temp: 0.0,
                 is_solid: false,
@@ -66,7 +67,8 @@ impl CellInfo {
         let reg = MaterialRegistry::instance();
         let mat = reg.get(cell.material);
         Self {
-            x, y,
+            x,
+            y,
             material: mat.name.to_string(),
             temp: cell.temp,
             is_solid: mat.solid,
@@ -78,18 +80,23 @@ impl CellInfo {
 
 pub fn entity_info(e: &crate::entity::entity::Entity) -> EntityInfo {
     let (px, py) = e.center();
-    let bodies: Vec<SubBodyInfo> = e.bodies.iter().enumerate().map(|(i, b)| {
-        let reg = MaterialRegistry::instance();
-        SubBodyInfo {
-            idx: i,
-            pos: [b.x, b.y],
-            vel: [b.vx(), b.vy()],
-            health: b.health,
-            alive: b.alive,
-            on_fire: b.on_fire,
-            material: reg.get(b.material).name.to_string(),
-        }
-    }).collect();
+    let bodies: Vec<SubBodyInfo> = e
+        .bodies
+        .iter()
+        .enumerate()
+        .map(|(i, b)| {
+            let reg = MaterialRegistry::instance();
+            SubBodyInfo {
+                idx: i,
+                pos: [b.x, b.y],
+                vel: [b.vx(), b.vy()],
+                health: b.health,
+                alive: b.alive,
+                on_fire: b.on_fire,
+                material: reg.get(b.material).name.to_string(),
+            }
+        })
+        .collect();
 
     EntityInfo {
         id: e.id,
@@ -107,7 +114,9 @@ pub fn entity_info(e: &crate::entity::entity::Entity) -> EntityInfo {
 pub fn build_game_state(game: &Game, view_w: usize, view_h: usize) -> GameState {
     let player_info = game.player.entity(&game.entities).map(entity_info);
 
-    let entities: Vec<EntityInfo> = game.entities.all()
+    let entities: Vec<EntityInfo> = game
+        .entities
+        .all()
         .iter()
         .filter(|e| e.id != game.player.entity_id)
         .map(entity_info)
@@ -129,17 +138,27 @@ pub fn build_game_state(game: &Game, view_w: usize, view_h: usize) -> GameState
     }
 }
 
-pub fn render_view(grid: &Grid, entities: &EntityManager, cam_x: i32, cam_y: i32, vw: usize, vh: usize) -> String {
+pub fn render_view(
+    grid: &Grid,
+    entities: &EntityManager,
+    cam_x: i32,
+    cam_y: i32,
+    vw: usize,
+    vh: usize,
+) -> String {
     let mut entity_map = std::collections::HashMap::new();
     for e in entities.all() {
         for b in &e.bodies {
-            if !b.alive { continue; }
+            if !b.alive {
+                continue;
+            }
             let sx = b.x as i32 - cam_x;
             let sy = b.y as i32 - cam_y;
             if sx >= 0 && sx < vw as i32 && sy >= 0 && sy < vh as i32 {
                 let ch = match e.kind {
                     EntityKind::Player if e.alive => '@',
                     EntityKind::Goblin if e.alive => 'g',
+                    EntityKind::Slime if e.alive => 's',
                     _ => '%',
                 };
                 entity_map.insert((sx, sy), ch);
@@ -190,6 +209,7 @@ pub fn entity_kind_name(kind: EntityKind) -> &'static str {
     match kind {
         EntityKind::Player => "Player",
         EntityKind::Goblin => "Goblin",
+        EntityKind::Slime => "Slime",
         EntityKind::Corpse => "Corpse",
     }
 }
@@ -198,6 +218,7 @@ pub fn parse_entity_kind(name: &str) -> Option<EntityKind> {
     match name.to_lowercase().as_str() {
         "player" => Some(EntityKind::Player),
         "goblin" => Some(EntityKind::Goblin),
+        "slime" => Some(EntityKind::Slime),
         "corpse" => Some(EntityKind::Corpse),
         _ => None,
     }

src/entity/body_template.rs

@@ -171,6 +171,41 @@ impl BodyTemplate {
         }
     }
 
+    pub fn slime() -> Self {
+        let parts = vec![
+            p!(-2, -1, 60, 180, 80, "body"),
+            p!(-1, -2, 80, 200, 100, "body"),
+            p!(0, -2, 90, 210, 110, "body"),
+            p!(1, -2, 80, 200, 100, "body"),
+            p!(2, -1, 60, 180, 80, "body"),
+            p!(-2, 0, 70, 190, 90, "body"),
+            p!(-1, 0, 100, 220, 130, "body"),
+            p!(0, 0, 110, 230, 140, "body"),
+            p!(1, 0, 100, 220, 130, "body"),
+            p!(2, 0, 70, 190, 90, "body"),
+            p!(-2, 1, 50, 170, 70, "body"),
+            p!(-1, 1, 80, 200, 100, "body"),
+            p!(0, 1, 90, 210, 110, "body"),
+            p!(1, 1, 80, 200, 100, "body"),
+            p!(2, 1, 50, 170, 70, "body"),
+            p!(-1, 2, 40, 160, 60, "body"),
+            p!(0, 2, 50, 170, 70, "body"),
+            p!(1, 2, 40, 160, 60, "body"),
+            p!(-1, -1, 120, 230, 150, "eye"),
+            p!(1, -1, 120, 230, 150, "eye"),
+        ];
+
+        let n = parts.len();
+        Self {
+            name: "slime".to_string(),
+            half_w: 3.0,
+            half_h: 2.0,
+            radius: 0.5,
+            parts,
+            constraints: Self::auto_constraints(n),
+        }
+    }
+
     pub fn boulder() -> Self {
         let parts = vec![
             p!(-1, -2, 100, 100, 110, "rock"),
@@ -311,6 +346,7 @@ pub fn template_for_kind(kind: EntityKind) -> BodyTemplate {
     match kind {
         EntityKind::Player => BodyTemplate::humanoid_player(),
         EntityKind::Goblin => BodyTemplate::humanoid_goblin(),
+        EntityKind::Slime => BodyTemplate::slime(),
         EntityKind::Corpse => BodyTemplate::humanoid_player(),
     }
 }

src/entity/entity.rs

@@ -7,6 +7,7 @@ pub type EntityId = u32;
 pub enum EntityKind {
     Player,
     Goblin,
+    Slime,
     Corpse,
 }
 
@@ -90,7 +91,10 @@ impl Entity {
                 b.set_vel(cvx + (b.x - self.cx) * 0.3, cvy + (b.y - self.cy) * 0.3);
             }
         }
-        if self.kind == EntityKind::Player || self.kind == EntityKind::Goblin {
+        if self.kind == EntityKind::Player
+            || self.kind == EntityKind::Goblin
+            || self.kind == EntityKind::Slime
+        {
             self.kind = EntityKind::Corpse;
         }
     }
@@ -176,6 +180,10 @@ impl EntityManager {
                 e.max_health = 40.0;
                 e.health = 40.0;
             }
+            EntityKind::Slime => {
+                e.max_health = 25.0;
+                e.health = 25.0;
+            }
             EntityKind::Corpse => {
                 e.alive = false;
                 e.rigid = false;

src/game.rs

@@ -1,14 +1,14 @@
 use std::time::{Duration, Instant};
 
-use crate::entity::{EntityManager, EntityKind};
+use crate::entity::player::Player;
+use crate::entity::{EntityKind, EntityManager};
 use crate::input::{Action, InputHandler};
-use crate::physics::verlet::VerletSolver;
 use crate::physics::collision::resolve_grid_collision;
+use crate::physics::verlet::VerletSolver;
 use crate::render::Renderer;
 use crate::world::cell::MaterialId;
-use crate::world::grid::Grid;
 use crate::world::cellular::CellularAutomaton;
-use crate::entity::player::Player;
+use crate::world::grid::Grid;
 
 pub struct Game {
     pub grid: Grid,
@@ -52,8 +52,10 @@ impl Game {
         let h = self.grid.height;
 
         for x in 0..w {
-            self.grid.set_material(x as i32, (h - 1) as i32, MaterialId::Stone);
-            self.grid.set_material(x as i32, (h - 2) as i32, MaterialId::Dirt);
+            self.grid
+                .set_material(x as i32, (h - 1) as i32, MaterialId::Stone);
+            self.grid
+                .set_material(x as i32, (h - 2) as i32, MaterialId::Dirt);
         }
 
         for x in 0..w {
@@ -101,7 +103,8 @@ impl Game {
             self.grid.set_material(wood_x + 4, y, MaterialId::Wood);
         }
         for x in wood_x..=wood_x + 4 {
-            self.grid.set_material(x, wood_surface - 8, MaterialId::Wood);
+            self.grid
+                .set_material(x, wood_surface - 8, MaterialId::Wood);
         }
 
         // Sand dune (right of center)
@@ -145,7 +148,9 @@ impl Game {
         let surface_x = cx as i32;
         let mut surface_y = h as i32 - 3;
         for y in 0..h as i32 {
-            if self.grid.get(surface_x, y).is_solid() && self.grid.get(surface_x, y).material != MaterialId::Stone {
+            if self.grid.get(surface_x, y).is_solid()
+                && self.grid.get(surface_x, y).material != MaterialId::Stone
+            {
                 surface_y = y;
                 break;
             }
@@ -224,7 +229,11 @@ impl Game {
                                 if let Some(m) = mat {
                                     self.grid.set_material(cx + dx, cy + dy, m);
                                 } else {
-                                    self.grid.set(cx + dx, cy + dy, crate::world::cell::Cell::empty());
+                                    self.grid.set(
+                                        cx + dx,
+                                        cy + dy,
+                                        crate::world::cell::Cell::empty(),
+                                    );
                                 }
                             }
                         }
@@ -293,12 +302,107 @@ impl Game {
         self.ca.step(&mut self.grid);
 
         self.update_entities();
+        self.update_slime_ai();
+        self.update_combat();
 
         self.apply_world_damage();
 
         if self.tick % 30 == 0 {
             self.try_spawn_goblin();
         }
+        if self.tick % 45 == 0 {
+            self.try_spawn_slime();
+        }
+    }
+
+    fn update_slime_ai(&mut self) {
+        let (px, py) = self.player.center(&self.entities);
+        let tick = self.tick;
+
+        let slime_data: Vec<(usize, f32, f32, bool, f32)> = self
+            .entities
+            .all()
+            .iter()
+            .enumerate()
+            .filter(|(_, e)| e.alive && e.kind == EntityKind::Slime)
+            .map(|(i, e)| (i, e.cx, e.cy, e.rigid, e.health))
+            .collect();
+
+        for (idx, sx, sy, rigid, health) in slime_data {
+            if !rigid {
+                continue;
+            }
+            let dx = px - sx;
+            let dy = py - sy;
+            let dist = (dx * dx + dy * dy).sqrt();
+            if dist < 0.5 {
+                continue;
+            }
+
+            let jump_phase = tick % 60;
+            if jump_phase == 0 && dist < 40.0 {
+                let dir_x = dx / dist;
+                let dir_y = dy / dist;
+                let jump_power = 0.8 + (1.0 - dist / 40.0).min(0.5) * 0.5;
+                if let Some(e) = self.entities.all_mut().get_mut(idx) {
+                    e.set_horizontal_vel(dir_x * jump_power);
+                    e.set_vertical_vel(-jump_power * 0.8);
+                }
+            } else if jump_phase == 30 {
+                if let Some(e) = self.entities.all_mut().get_mut(idx) {
+                    e.set_horizontal_vel(0.0);
+                }
+            }
+        }
+    }
+
+    fn update_combat(&mut self) {
+        let player_id = self.player.entity_id;
+        let player_center = self.player.center(&self.entities);
+        let player_half_w = self
+            .entities
+            .get(player_id)
+            .map(|e| e.half_w)
+            .unwrap_or(3.0);
+        let player_half_h = self
+            .entities
+            .get(player_id)
+            .map(|e| e.half_h)
+            .unwrap_or(6.0);
+
+        let enemy_data: Vec<(usize, EntityKind, f32, f32, f32, f32)> = self
+            .entities
+            .all()
+            .iter()
+            .enumerate()
+            .filter(|(_, e)| {
+                e.alive && e.kind != EntityKind::Player && e.kind != EntityKind::Corpse
+            })
+            .map(|(i, e)| (i, e.kind, e.cx, e.cy, e.half_w, e.half_h))
+            .collect();
+
+        for (idx, kind, ex, ey, ew, eh) in enemy_data {
+            let dx = (ex - player_center.0).abs();
+            let dy = (ey - player_center.1).abs();
+            if dx < ew + player_half_w && dy < eh + player_half_h {
+                if self.tick % 20 == 0 {
+                    let damage = match kind {
+                        EntityKind::Goblin => 8.0,
+                        EntityKind::Slime => 5.0,
+                        _ => 0.0,
+                    };
+                    if damage > 0.0 {
+                        if let Some(p) = self.entities.get_mut(player_id) {
+                            p.take_damage(damage);
+                        }
+                        let knockback_dir = if player_center.0 < ex { -1.0 } else { 1.0 };
+                        if let Some(p) = self.entities.get_mut(player_id) {
+                            p.set_horizontal_vel(knockback_dir * 0.5);
+                        }
+                    }
+                }
+            }
+        }
     }
 
     fn update_entities(&mut self) {
@@ -374,16 +478,23 @@ impl Game {
                 // Blocked — resolve X
                 let (resolved_x, hit) = self.resolve_aabb_x(idx, nx, ny, half_w, half_h, nvx);
                 nx = resolved_x;
-                if hit { nvx = 0.0; }
+                if hit {
+                    nvx = 0.0;
+                }
             }
         }
 
         // Step 2: Vertical movement
         ny += nvy;
-        let (resolved_y, hit_floor, hit_ceiling) = self.resolve_aabb_y(idx, nx, ny, half_w, half_h, nvy > 0.0);
+        let (resolved_y, hit_floor, hit_ceiling) =
+            self.resolve_aabb_y(idx, nx, ny, half_w, half_h, nvy > 0.0);
         ny = resolved_y;
-        if hit_floor { nvy = 0.0; }
-        if hit_ceiling { nvy = 0.0; }
+        if hit_floor {
+            nvy = 0.0;
+        }
+        if hit_ceiling {
+            nvy = 0.0;
+        }
 
         // Check material contacts
         let (touching_lava, touching_fire, touching_acid, in_liquid) = {
@@ -398,12 +509,22 @@ impl Game {
             let max_y = (ny + half_h).ceil() as i32;
             for y in min_y..=max_y {
                 for x in min_x..=max_x {
-                    if !grid.in_bounds(x, y) { continue; }
+                    if !grid.in_bounds(x, y) {
+                        continue;
+                    }
                     let cell = grid.get(x, y);
-                    if cell.material == MaterialId::Lava { tl = true; }
-                    if cell.material == MaterialId::Fire { tf = true; }
-                    if cell.material == MaterialId::Acid { ta = true; }
-                    if cell.is_liquid() { il = true; }
+                    if cell.material == MaterialId::Lava {
+                        tl = true;
+                    }
+                    if cell.material == MaterialId::Fire {
+                        tf = true;
+                    }
+                    if cell.material == MaterialId::Acid {
+                        ta = true;
+                    }
+                    if cell.is_liquid() {
+                        il = true;
+                    }
                 }
             }
             (tl, tf, ta, il)
@@ -424,7 +545,9 @@ impl Game {
                 for b in &mut e.bodies {
                     if b.alive {
                         b.health -= 0.5;
-                        if !b.on_fire { b.on_fire = true; }
+                        if !b.on_fire {
+                            b.on_fire = true;
+                        }
                     }
                 }
             }
@@ -432,13 +555,17 @@ impl Game {
                 for b in &mut e.bodies {
                     if b.alive {
                         b.health -= 0.15;
-                        if !b.on_fire && b.health < 80.0 { b.on_fire = true; }
+                        if !b.on_fire && b.health < 80.0 {
+                            b.on_fire = true;
+                        }
                     }
                 }
             }
             if touching_acid {
                 for b in &mut e.bodies {
-                    if b.alive { b.health -= 0.25; }
+                    if b.alive {
+                        b.health -= 0.25;
+                    }
                 }
             }
         }
@@ -458,9 +585,13 @@ impl Game {
 
         for y in min_y..=max_y {
             for x in min_x..=max_x {
-                if !grid.in_bounds(x, y) { continue; }
+                if !grid.in_bounds(x, y) {
+                    continue;
+                }
                 let cell = grid.get(x, y);
-                if !cell.is_solid() { continue; }
+                if !cell.is_solid() {
+                    continue;
+                }
                 let cl = x as f32;
                 let cr = (x + 1) as f32;
                 let ct = y as f32;
@@ -473,7 +604,15 @@ impl Game {
         false
     }
 
-    fn resolve_aabb_x(&self, _idx: usize, cx: f32, cy: f32, hw: f32, hh: f32, vx: f32) -> (f32, bool) {
+    fn resolve_aabb_x(
+        &self,
+        _idx: usize,
+        cx: f32,
+        cy: f32,
+        hw: f32,
+        hh: f32,
+        vx: f32,
+    ) -> (f32, bool) {
         let grid = &self.grid;
         let left = cx - hw;
         let right = cx + hw;
@@ -490,9 +629,13 @@ impl Game {
 
         for y in min_y..=max_y {
             for x in min_x..=max_x {
-                if !grid.in_bounds(x, y) { continue; }
+                if !grid.in_bounds(x, y) {
+                    continue;
+                }
                 let cell = grid.get(x, y);
-                if !cell.is_solid() { continue; }
+                if !cell.is_solid() {
+                    continue;
+                }
 
                 let cell_left = x as f32;
                 let cell_right = (x + 1) as f32;
@@ -532,7 +675,15 @@ impl Game {
         (new_cx, hit)
     }
 
-    fn resolve_aabb_y(&self, _idx: usize, cx: f32, cy: f32, hw: f32, hh: f32, moving_down: bool) -> (f32, bool, bool) {
+    fn resolve_aabb_y(
+        &self,
+        _idx: usize,
+        cx: f32,
+        cy: f32,
+        hw: f32,
+        hh: f32,
+        moving_down: bool,
+    ) -> (f32, bool, bool) {
         let grid = &self.grid;
         let left = cx - hw;
         let right = cx + hw;
@@ -550,9 +701,13 @@ impl Game {
 
         for y in min_y..=max_y {
             for x in min_x..=max_x {
-                if !grid.in_bounds(x, y) { continue; }
+                if !grid.in_bounds(x, y) {
+                    continue;
+                }
                 let cell = grid.get(x, y);
-                if !cell.is_solid() { continue; }
+                if !cell.is_solid() {
+                    continue;
+                }
 
                 let cell_left = x as f32;
                 let cell_right = (x + 1) as f32;
@@ -593,7 +748,12 @@ impl Game {
         (new_cy, hit_floor, hit_ceiling)
     }
 
-    fn update_ragdoll_entity(&mut self, idx: usize, solver: &crate::physics::verlet::VerletSolver, substeps: u32) {
+    fn update_ragdoll_entity(
+        &mut self,
+        idx: usize,
+        solver: &crate::physics::verlet::VerletSolver,
+        substeps: u32,
+    ) {
         let grid = &self.grid;
         let mut bodies = self.entities.all()[idx].bodies.clone();
         let constraints = self.entities.all()[idx].constraints.clone();
@@ -622,11 +782,15 @@ impl Game {
                 let result = resolve_grid_collision(grid, b);
                 if result.touching_lava {
                     b.health -= 0.5;
-                    if !b.on_fire { b.on_fire = true; }
+                    if !b.on_fire {
+                        b.on_fire = true;
+                    }
                 }
                 if result.touching_fire {
                     b.health -= 0.15;
-                    if !b.on_fire && b.health < 80.0 { b.on_fire = true; }
+                    if !b.on_fire && b.health < 80.0 {
+                        b.on_fire = true;
+                    }
                 }
                 if result.touching_acid {
                     b.health -= 0.25;
@@ -673,7 +837,12 @@ impl Game {
     }
 
     fn try_spawn_goblin(&mut self) {
-        let alive_goblins = self.entities.all().iter().filter(|e| e.alive && e.kind == EntityKind::Goblin).count();
+        let alive_goblins = self
+            .entities
+            .all()
+            .iter()
+            .filter(|e| e.alive && e.kind == EntityKind::Goblin)
+            .count();
         if alive_goblins >= 3 {
             return;
         }
@@ -703,4 +872,41 @@ impl Game {
             g.build_humanoid(spawn_x as f32, spawn_y as f32);
         }
     }
+
+    fn try_spawn_slime(&mut self) {
+        let alive_slimes = self
+            .entities
+            .all()
+            .iter()
+            .filter(|e| e.alive && e.kind == EntityKind::Slime)
+            .count();
+        if alive_slimes >= 2 {
+            return;
+        }
+
+        let (px, _py) = self.player.center(&self.entities);
+        let spawn_x = px as i32 + if px as i32 % 2 == 0 { -18 } else { 18 };
+        if !self.grid.in_bounds(spawn_x, 0) {
+            return;
+        }
+
+        let mut surface_y = self.grid.height as i32 - 3;
+        for y in 0..self.grid.height as i32 {
+            let cell = self.grid.get(spawn_x, y);
+            if cell.is_solid() && cell.material != MaterialId::Stone {
+                surface_y = y;
+                break;
+            }
+        }
+        let spawn_y = surface_y - 3;
+
+        if !self.grid.in_bounds(spawn_x, spawn_y) {
+            return;
+        }
+
+        let id = self.entities.spawn(EntityKind::Slime);
+        if let Some(s) = self.entities.get_mut(id) {
+            s.build_humanoid(spawn_x as f32, spawn_y as f32);
+        }
+    }
 }

src/render/terminal.rs

@@ -126,6 +126,7 @@ impl Renderer for TerminalRenderer {
                     let ch = match e.kind {
                         crate::entity::EntityKind::Player if e.alive => '@',
                         crate::entity::EntityKind::Goblin if e.alive => 'g',
+                        crate::entity::EntityKind::Slime if e.alive => 's',
                         _ => '%',
                     };
                     let fg = if e.on_fire {

src/render/vulkan.rs

@@ -217,6 +217,7 @@ impl VulkanRenderer {
                     let ch = match e.kind {
                         EntityKind::Player if e.alive => '@',
                         EntityKind::Goblin if e.alive => 'g',
+                        EntityKind::Slime if e.alive => 's',
                         _ => '%',
                     };
                     let fg = if e.on_fire {

tests/slime.rs

@@ -0,0 +1,138 @@
+use verbatim::ai::AiAction;
+use verbatim::ai::GameSession;
+
+fn setup() -> GameSession {
+    let mut s = GameSession::new_seeded(42);
+    s.init_empty();
+    s.clear_area(90, 90, 50, 50);
+    s.perform_action(&AiAction::FillRect {
+        x: 80,
+        y: 130,
+        w: 80,
+        h: 15,
+        material: "stone".into(),
+    });
+    s
+}
+
+#[test]
+fn slime_spawns_correctly() {
+    let mut s = setup();
+    s.perform_action(&AiAction::Spawn {
+        kind: "slime".into(),
+        x: 120.0,
+        y: 120.0,
+    });
+    let entities = s.get_entities();
+    let slime = entities.into_iter().find(|e| e.kind == "Slime");
+    assert!(slime.is_some(), "slime should exist after spawn");
+    let sl = slime.unwrap();
+    assert!(sl.alive, "slime should be alive");
+    assert_eq!(sl.max_health, 25.0, "slime max health should be 25");
+}
+
+#[test]
+fn slime_takes_damage_and_dies() {
+    let mut s = setup();
+    s.perform_action(&AiAction::Spawn {
+        kind: "slime".into(),
+        x: 120.0,
+        y: 120.0,
+    });
+    s.step(10);
+    let id = s
+        .get_entities()
+        .into_iter()
+        .find(|e| e.kind == "Slime")
+        .unwrap()
+        .id;
+    s.perform_action(&AiAction::DamageEntity { id, amount: 25.0 });
+    s.step(1);
+    let entities = s.get_entities();
+    let sl = entities.into_iter().find(|e| e.id == id).unwrap();
+    assert!(!sl.alive, "slime should die after 25 damage");
+    assert_eq!(sl.kind, "Corpse", "dead slime should become corpse");
+}
+
+#[test]
+fn slime_jumps_toward_player() {
+    let mut s = setup();
+    s.step(30);
+    let player = s.get_player().unwrap();
+    let px = player.pos[0];
+    s.perform_action(&AiAction::Spawn {
+        kind: "slime".into(),
+        x: px + 10.0,
+        y: 120.0,
+    });
+    s.step(10);
+    let entities = s.get_entities();
+    let slime = entities.into_iter().find(|e| e.kind == "Slime" && e.alive);
+    assert!(slime.is_some(), "slime should be alive");
+    let slime_y_before = slime.unwrap().pos[1];
+    s.step(60);
+    let entities = s.get_entities();
+    let slime_after = entities.into_iter().find(|e| e.kind == "Slime" && e.alive);
+    if let Some(sl) = slime_after {
+        assert!(
+            sl.pos[1] < slime_y_before + 5.0 || sl.pos[0] != px + 10.0,
+            "slime should have moved (jumped) from original position"
+        );
+    }
+}
+
+#[test]
+fn slime_deals_contact_damage_to_player() {
+    let mut s = setup();
+    s.step(30);
+    let player = s.get_player().unwrap();
+    let hp_before = player.health;
+    s.perform_action(&AiAction::Spawn {
+        kind: "slime".into(),
+        x: player.pos[0] + 1.0,
+        y: player.pos[1],
+    });
+    s.step(60);
+    let player_after = s.get_player().unwrap();
+    assert!(
+        player_after.health < hp_before,
+        "player should take damage from slime contact: {} -> {}",
+        hp_before,
+        player_after.health
+    );
+}
+
+#[test]
+fn slime_template_has_correct_shape() {
+    use verbatim::entity::body_template::BodyTemplate;
+    let t = BodyTemplate::slime();
+    assert_eq!(t.name, "slime");
+    assert!(
+        t.parts.len() >= 15,
+        "slime should have 15+ parts, got {}",
+        t.parts.len()
+    );
+    assert!(
+        t.parts.iter().any(|p| p.label == "eye"),
+        "slime should have eyes"
+    );
+}
+
+#[test]
+fn slime_count_in_world() {
+    let mut s = setup();
+    for i in 0..3 {
+        s.perform_action(&AiAction::Spawn {
+            kind: "slime".into(),
+            x: 100.0 + i as f32 * 10.0,
+            y: 120.0,
+        });
+    }
+    s.step(10);
+    let slimes = s
+        .get_entities()
+        .into_iter()
+        .filter(|e| e.kind == "Slime")
+        .count();
+    assert_eq!(slimes, 3, "should have 3 slimes");
+}