diff --git a/src/core/bubble.rs b/src/core/bubble.rs
index 44f3724..50ae394 100644
--- a/src/core/bubble.rs
+++ b/src/core/bubble.rs
@@ -5,6 +5,7 @@ use rand::Rng;
 
 use crate::{
     core::{
+        game_state::DispawnOnGameOver,
         kirby::Kirby,
         life::{DamageDealer, Life},
         wave::BubbleSplash,
@@ -13,7 +14,7 @@ use crate::{
 };
 
 #[derive(Component)]
-#[require(Sprite, PhysicsBody, DensityObject, Life, DamageDealer, SphereCollider)]
+#[require(Sprite, PhysicsBody, DensityObject, Life, DamageDealer, SphereCollider, DispawnOnGameOver)]
 pub struct Bubble {
     move_force: f32,
 }
diff --git a/src/core/collectible.rs b/src/core/collectible.rs
index 3c40553..db74610 100644
--- a/src/core/collectible.rs
+++ b/src/core/collectible.rs
@@ -1,6 +1,7 @@
 use std::path::Path;
 use std::time::Duration;
 
+use crate::core::game_state::{DispawnOnGameOver, GameStartupSet, GameState};
 use crate::core::kirby::{Kirby, kirby_spawn};
 use crate::physics::sphere_collider::SphereCollider;
 use bevy::prelude::*;
@@ -17,7 +18,7 @@ pub enum CollectableType {
 }
 
 #[derive(Component)]
-#[require(SphereCollider, Sprite)]
+#[require(SphereCollider, Sprite, DispawnOnGameOver)]
 pub struct Collectable(CollectableType);
 
 // Not a system.
@@ -83,6 +84,7 @@ fn new_kirby(kirby_pos: Vec3, commands: &mut Commands) {
 }
 
 #[derive(Component)]
+#[require(DispawnOnGameOver)]
 struct KirbySpawnHandler {
     timer: Timer,
     position: Vec3,
@@ -108,7 +110,7 @@ pub struct CollectablePlugin;
 
 impl Plugin for CollectablePlugin {
     fn build(&self, app: &mut App) {
-        app.add_systems(Startup, collectable_spawner_init)
+        app.add_systems(OnEnter(GameState::Starting), collectable_spawner_init.in_set(GameStartupSet))
             .add_systems(FixedUpdate, collectable_actions_system)
             .add_systems(Update, kirby_spawn_timer);
     }
diff --git a/src/core/game_state.rs b/src/core/game_state.rs
new file mode 100644
index 0000000..8d80217
--- /dev/null
+++ b/src/core/game_state.rs
@@ -0,0 +1,87 @@
+use bevy::{ecs::system::SystemParam, prelude::*};
+
+use crate::core::{kirby::Kirby, wave::BubbleWaves};
+
+#[derive(Event)]
+struct EndGameEvent {
+    pub reason: EndGameReason,
+}
+
+#[derive(Clone, Copy, Debug)]
+enum EndGameReason {
+    Die,
+    Victory,
+}
+
+fn no_kirbies_emetter(mut commands: Commands, query: Query<(), With<Kirby>>) {
+    if query.is_empty() {
+        commands.trigger(EndGameEvent { reason: EndGameReason::Die });
+    };
+}
+
+#[derive(States, Default, Debug, Clone, PartialEq, Eq, Hash)]
+pub enum GameState {
+    #[default]
+    Starting,
+    Running,
+    Paused,
+}
+
+#[derive(SystemSet, Debug, Hash, PartialEq, Eq, Clone)]
+pub struct GameStartupSet;
+
+#[derive(Component, Default)]
+pub struct DispawnOnGameOver;
+
+pub trait Resetable {
+    fn reset(&mut self);
+}
+
+fn reset_resource<T: Resource + Resetable>(mut res: ResMut<T>) {
+    res.reset();
+}
+
+#[derive(SystemParam)]
+struct GameRes<'w> {
+    bubble_waves: ResMut<'w, BubbleWaves>,
+}
+
+fn on_reset_world(
+    _: On<ResetWorldEvent>,
+    mut commands: Commands,
+    entities: Query<Entity, With<DispawnOnGameOver>>,
+    game_res: GameRes,
+) {
+    for e in &entities {
+        commands.entity(e).despawn();
+    }
+    reset_resource(game_res.bubble_waves);
+    println!("Set state");
+    commands.set_state(GameState::Starting);
+}
+
+#[derive(Event)]
+struct ResetWorldEvent;
+
+fn on_end_game(event: On<EndGameEvent>, mut commands: Commands) {
+    let reason = event.reason;
+    println!("end game reason {:?}", reason);
+    commands.trigger(ResetWorldEvent);
+}
+
+fn change_to_running_state(mut commands: Commands) {
+    println!("Running state !");
+    commands.set_state(GameState::Running);
+}
+
+pub struct GameEventsPlugin;
+
+impl Plugin for GameEventsPlugin {
+    fn build(&self, app: &mut App) {
+        app.init_state::<GameState>()
+            .add_systems(Update, no_kirbies_emetter.run_if(in_state(GameState::Running)))
+            .add_systems(OnEnter(GameState::Starting), change_to_running_state.after(GameStartupSet))
+            .add_observer(on_end_game)
+            .add_observer(on_reset_world);
+    }
+}
diff --git a/src/core/kirby.rs b/src/core/kirby.rs
index bf63599..45b2d06 100644
--- a/src/core/kirby.rs
+++ b/src/core/kirby.rs
@@ -1,20 +1,23 @@
+use crate::core::game_state::{GameStartupSet, DispawnOnGameOver};
 use bevy::prelude::*;
 
 const KIRBY_SCALE: f32 = 3.0;
 
 use crate::{
-    core::life::{DamageDealer, Life},
+    core::{
+        game_state::GameState,
+        life::{DamageDealer, Life},
+    },
     juice::animation::{AnimationIndices, AnimationTimer},
-    physics::physics_body::PhysicsBody,
-    physics::sphere_collider::SphereCollider,
+    physics::{physics_body::PhysicsBody, sphere_collider::SphereCollider},
 };
 
 #[derive(Component)]
-#[require(Transform, SphereCollider, DamageDealer)]
+#[require(Transform, SphereCollider, DamageDealer, DispawnOnGameOver)]
 pub struct SuckArea;
 
 #[derive(Component)]
-#[require(Sprite, PhysicsBody, SphereCollider, AnimationIndices, Life)]
+#[require(Sprite, PhysicsBody, SphereCollider, AnimationIndices, Life, DispawnOnGameOver)]
 pub struct Kirby {
     pub speed_force: f32,
     pub is_sucking: bool,
@@ -26,6 +29,7 @@ pub fn kirby_spawn_start(
     asset_server: Res<AssetServer>,
     mut texture_atlas_layouts: ResMut<Assets<TextureAtlasLayout>>,
 ) {
+    println!("Start Kirby");
     kirby_spawn(&mut commands, &asset_server, &mut texture_atlas_layouts, Vec3::ZERO);
     // kirby_spawn(&mut commands, &asset_server, &mut texture_atlas_layouts, Vec3 { x: 500.0, y: 0.0, z: 0.0 });
 }
@@ -52,7 +56,7 @@ pub fn kirby_spawn(
             SphereCollider::new(20.0),
             animation_indices,
             AnimationTimer(Timer::from_seconds(0.1, TimerMode::Repeating)),
-            Life::new(1000.0),
+            Life::new(10.0),
             Transform::from_translation(pos).with_scale(Vec3::splat(KIRBY_SCALE)),
         ))
         .id();
@@ -119,6 +123,7 @@ pub struct KirbyPlugin;
 
 impl Plugin for KirbyPlugin {
     fn build(&self, app: &mut App) {
-        app.add_systems(Startup, kirby_spawn_start).add_systems(FixedUpdate, kirby_actions);
+        app.add_systems(OnEnter(GameState::Starting), kirby_spawn_start.in_set(GameStartupSet))
+            .add_systems(FixedUpdate, kirby_actions);
     }
 }
diff --git a/src/core/life.rs b/src/core/life.rs
index dc3f3bd..838e907 100644
--- a/src/core/life.rs
+++ b/src/core/life.rs
@@ -1,13 +1,17 @@
 use bevy::prelude::*;
 
 use crate::{
-    core::bubble::Bubble,
-    core::counter::{BubbleExplodedCountThisFrame, BubbleSuckedCountThisFrame, KirbyHitCountThisFrame},
-    core::kirby::{Kirby, SuckArea},
+    core::{
+        bubble::Bubble,
+        counter::{BubbleExplodedCountThisFrame, BubbleSuckedCountThisFrame, KirbyHitCountThisFrame},
+        game_state::DispawnOnGameOver,
+        kirby::{Kirby, SuckArea},
+    },
     physics::sphere_collider::SphereCollider,
 };
 
 #[derive(Component)]
+#[require(DispawnOnGameOver)]
 pub struct Life {
     max_life: f32,
     current_life: f32,
@@ -42,7 +46,7 @@ pub fn despawn_if_dead(mut commands: Commands, query: Query<(Entity, &Life)>) {
 }
 
 #[derive(Component, Default)]
-#[require(SphereCollider)]
+#[require(SphereCollider, DispawnOnGameOver)]
 pub struct DamageDealer {
     damage_strength: f32,
 }
diff --git a/src/core/mod.rs b/src/core/mod.rs
index b30d8d8..57d5538 100644
--- a/src/core/mod.rs
+++ b/src/core/mod.rs
@@ -1,6 +1,7 @@
 pub mod bubble;
 pub mod collectible;
 pub mod counter;
+pub mod game_state;
 pub mod kirby;
 pub mod life;
 pub mod wave;
diff --git a/src/core/wave.rs b/src/core/wave.rs
index 01def64..e4e4ffa 100644
--- a/src/core/wave.rs
+++ b/src/core/wave.rs
@@ -4,7 +4,12 @@ use bevy::prelude::*;
 use rand::distr::slice::Empty;
 
 use crate::{
-    core::bubble::{Bubble, bubble_spawn_wave},
+    core::{
+        bubble::{Bubble, bubble_spawn_wave},
+        game_state::Resetable,
+        kirby::Kirby,
+        life::Life,
+    },
     map::map::{BOTTOM, LEFT, RIGHT, TOP},
 };
 
@@ -50,7 +55,7 @@ const GREEN_BUBBLE: BubbleType = BubbleType {
 
 #[derive(Resource)]
 pub struct BubbleWaves {
-    pub waves: Vec<Vec<BubbleSplash>>,
+    waves: Vec<Vec<BubbleSplash>>,
     pub current_wave: usize,
 }
 
@@ -75,6 +80,12 @@ fn get_bubble_waves() -> BubbleWaves {
     }
 }
 
+impl Resetable for BubbleWaves {
+    fn reset(&mut self) {
+        *self = get_bubble_waves();
+    }
+}
+
 fn no_ennemy_left(bubble_query: Query<(), With<Bubble>>) -> bool {
     bubble_query.is_empty()
 }
@@ -88,10 +99,16 @@ fn change_wave(mut bubble_wave: ResMut<BubbleWaves>, mut commands: Commands, ass
     bubble_spawn_wave(&mut commands, &asset_server, bubble_wave.waves[bubble_wave.current_wave].as_slice());
 }
 
+fn heal_kirby(query: Query<&mut Life, With<Kirby>>) {
+    for mut kirby_life in query {
+        kirby_life.heal(f32::MAX);
+    }
+}
+
 pub struct WavePlugin;
 
 impl Plugin for WavePlugin {
     fn build(&self, app: &mut App) {
-        app.insert_resource(get_bubble_waves()).add_systems(Update, change_wave.run_if(no_ennemy_left));
+        app.insert_resource(get_bubble_waves()).add_systems(Update, (change_wave, heal_kirby).run_if(no_ennemy_left));
     }
 }
diff --git a/src/juice/animation.rs b/src/juice/animation.rs
index 5ad1bc6..49cb4a5 100644
--- a/src/juice/animation.rs
+++ b/src/juice/animation.rs
@@ -1,7 +1,8 @@
+use crate::core::game_state::DispawnOnGameOver;
 use bevy::prelude::*;
-// Source : https://bevy.org/examples/2d-rendering/sprite-sheet/
 
 #[derive(Component, Default)]
+#[require(DispawnOnGameOver)]
 pub struct AnimationIndices {
     pub first: usize,
     pub last: usize,
@@ -15,6 +16,7 @@ impl AnimationIndices {
 }
 
 #[derive(Component, Deref, DerefMut)]
+#[require(DispawnOnGameOver)]
 pub struct AnimationTimer(pub Timer);
 
 pub fn animate_sprite(time: Res<Time>, mut query: Query<(&AnimationIndices, &mut AnimationTimer, &mut Sprite)>) {
diff --git a/src/main.rs b/src/main.rs
index cb36c77..b071cc6 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -21,6 +21,7 @@ mod juice;
 use juice::animation::animate_sprite;
 use juice::camera::MyCameraPlugin;
 
+use crate::core::game_state::GameEventsPlugin;
 use crate::core::wave::WavePlugin;
 
 fn main() {
@@ -34,6 +35,7 @@ fn main() {
             }),
             ..default()
         }))
+        .add_plugins(GameEventsPlugin)
         .add_plugins(CounterPlugin)
         .add_plugins(KirbyPlugin)
         .add_plugins(DensityGridPlugin)
diff --git a/src/physics/density_grid.rs b/src/physics/density_grid.rs
index 536136b..f163acf 100644
--- a/src/physics/density_grid.rs
+++ b/src/physics/density_grid.rs
@@ -4,7 +4,7 @@ use bevy::prelude::*;
 use rand::Rng;
 
 pub static MAX_MAP_WIDTH: usize = 1024;
-use crate::physics::physics_body::PhysicsBody;
+use crate::{core::game_state::GameState, physics::physics_body::PhysicsBody};
 
 const CELL_SIZE: usize = 8;
 const MAX_MAP_SIZE: usize = MAX_MAP_WIDTH * 2;
@@ -78,11 +78,9 @@ pub fn density_grid_force(
                 let index = get_index_from_uvec2(neighbor_cell);
                 let density = density_grid.grid[index];
 
-                // println!("offset : {:?} density: {:?}", offset.as_vec2(), density);
                 density_gradient += offset.as_vec2() * density as f32;
             }
         }
-        // println!("density : {:?}", density_gradient);
         density_gradient += density_obj.random_offset; // To not have a "grid" thingy
         physics_body.force -= density_gradient * DENSITY_FORCE_SCALE;
     }
@@ -93,7 +91,7 @@ pub struct DensityGridPlugin;
 impl Plugin for DensityGridPlugin {
     fn build(&self, app: &mut App) {
         app.insert_resource(DensityGrid::new())
-            .add_systems(PostStartup, init_density_object)
+            .add_systems(OnExit(GameState::Starting), init_density_object)
             .add_systems(FixedUpdate, (density_grid_update, density_grid_force).chain());
     }
 }
diff --git a/src/physics/physics_body.rs b/src/physics/physics_body.rs
index 7bb53ea..21c56fc 100644
--- a/src/physics/physics_body.rs
+++ b/src/physics/physics_body.rs
@@ -1,9 +1,10 @@
 use bevy::prelude::*;
 
+use crate::core::game_state::DispawnOnGameOver;
 use crate::map::map::MapBounds;
 
 #[derive(Component)]
-#[require(Transform)]
+#[require(Transform, DispawnOnGameOver)]
 pub struct PhysicsBody {
     pub mass: f32,
     pub force: Vec2,