diff --git a/assets/audio/monster-footsteps.ogg b/assets/audio/monster-footsteps.ogg
new file mode 100644
index 0000000..3cf1f5c
Binary files /dev/null and b/assets/audio/monster-footsteps.ogg differ
diff --git a/assets/main.assets.ron b/assets/main.assets.ron
index d01bbfe..99637d0 100644
--- a/assets/main.assets.ron
+++ b/assets/main.assets.ron
@@ -2,6 +2,7 @@
     "lebron": File (path: "images/KingLebron.png"),
     "flash_hold_4": File (path: "images/pixelart/Flashlight_hold_4.png"),
     "flash_hold_4_pressed": File (path: "images/pixelart/Flashlight_click_4.png"),
+    "monster_footsteps": File (path: "audio/monster-footsteps.ogg"),
     "house": File (path: "meshes/House.glb"),
     "flashlight_click": File (path: "audio/flashlight-switch.ogg"),
     "library": Folder (
diff --git a/src/asset_loading/mod.rs b/src/asset_loading/mod.rs
index a2ab2e5..0efc560 100644
--- a/src/asset_loading/mod.rs
+++ b/src/asset_loading/mod.rs
@@ -31,6 +31,8 @@ pub(super) fn plugin(app: &mut App) {
 pub(crate) struct AudioAssets {
     #[asset(key = "flashlight_click")]
     pub(crate) flash_click: Handle<AudioSource>,
+    #[asset(key = "monster_footsteps")]
+    pub(crate) monster_footsteps: Handle<AudioSource>,
 }
 
 #[derive(AssetCollection, Resource, Clone)]
diff --git a/src/main.rs b/src/main.rs
index 4554a3a..ddaf90c 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -10,6 +10,7 @@ mod main_menu;
 mod player;
 mod util;
 mod debugging;
+mod monster;
 
 fn main() {
     App::new()
@@ -22,12 +23,13 @@ fn main() {
             RapierPhysicsPlugin::<NoUserData>::default(),
             // RapierDebugRenderPlugin::default(),
             player::plugin,
+            monster::plugin,
             // debugging::plugin
         ))
         .init_state::<GameState>()
         .insert_resource(AmbientLight {
             color: Color::srgba(0.8, 0.8, 1.0, 1.0),
-            // brightness: 10.0, 
+            // brightness: 11.0, 
             brightness: 80.0,
         })
         .add_systems(OnEnter(GameState::Playing), setup)
diff --git a/src/monster.rs b/src/monster.rs
new file mode 100644
index 0000000..4acf752
--- /dev/null
+++ b/src/monster.rs
@@ -0,0 +1,355 @@
+use std::time::Duration;
+
+use bevy::{
+    prelude::*, 
+    time::Stopwatch,
+};
+use bevy_kira_audio::{prelude::Volume, Audio, AudioControl, AudioTween};
+use bevy_rapier3d::prelude::*;
+use rand::prelude::*;
+
+use crate::{
+    asset_loading::AudioAssets,
+    player::Player,
+    GameState
+};
+
+// Monster states and behavior configuration
+#[derive(Debug, Component)]
+pub struct Monster {
+    pub speed: f32,
+    pub detection_range: f32,
+    pub state_timer: Timer,
+    pub footstep_timer: Timer,
+    pub state: MonsterState,
+}
+
+#[derive(Debug, Clone, PartialEq)]
+pub enum MonsterState {
+    Lurking,
+    Hunting, 
+    Wandering,
+    Dormant,
+}
+
+impl Default for Monster {
+    fn default() -> Self {
+        Self {
+            speed: 2.0,
+            detection_range: 15.0,
+            state_timer: Timer::from_seconds(1.0, TimerMode::Once),
+            footstep_timer: Timer::from_seconds(3.0, TimerMode::Repeating),
+            state: MonsterState::Dormant,
+        }
+    }
+}
+
+#[derive(Debug, Component, Default)]
+pub struct MonsterPathfinding {
+    pub current_target: Option<Vec3>,
+    pub wander_target_timer: Timer,
+}
+
+#[derive(Debug, Component, Default)]
+pub struct DangerIndicator {
+    pub last_sound_timer: Stopwatch,
+}
+
+pub fn plugin(app: &mut App) {
+    app
+        .add_systems(OnEnter(GameState::Playing), spawn_monster)
+        .add_systems(
+            Update,
+            (
+                update_monster_state,
+                move_monster,
+                play_monster_sounds,
+            ).run_if(in_state(GameState::Playing)),
+        );
+}
+
+fn spawn_monster(
+    mut commands: Commands,
+    // mut meshes: ResMut<Assets<Mesh>>,
+    // mut materials: ResMut<Assets<StandardMaterial>>,
+) {
+    let spawn_position = Vec3::new(20.0, 0.5, 20.0);
+    
+    commands.spawn((
+        Monster::default(),
+        MonsterPathfinding {
+            current_target: None,
+            wander_target_timer: Timer::from_seconds(5.0, TimerMode::Repeating),
+        },
+        DangerIndicator::default(),
+        RigidBody::Dynamic,
+        Collider::capsule(Vec3::new(0.0, -0.5, 0.0), Vec3::new(0.0, 1.0, 0.0), 0.6),
+        Velocity::zero(),
+        LockedAxes::ROTATION_LOCKED,
+        Damping {
+            linear_damping: 1.0,
+            angular_damping: 1.0,
+        },
+        Transform::from_translation(spawn_position),
+    ));
+}
+
+fn update_monster_state(
+    time: Res<Time>,
+    mut monster_query: Query<(&mut Monster, &Transform, &mut MonsterPathfinding, &mut DangerIndicator), Without<Player>>,
+    player_query: Query<&Transform, With<Player>>,
+) {
+    let mut rand = rand::rng();
+    
+    if let Ok((mut monster, monster_transform, mut pathfinding, mut danger)) = monster_query.get_single_mut() {
+        let player_pos = if let Ok(player_transform) = player_query.get_single() {
+            Some(player_transform.translation)
+        } else {
+            None
+        };
+        
+        monster.state_timer.tick(time.delta());
+        
+        // when timer expires, potentially change state
+        if monster.state_timer.just_finished() {
+            let next_state = match monster.state {
+                MonsterState::Dormant => {
+                    // 70% chance to start lurking
+                    if rand.random_bool(0.85) {
+                        MonsterState::Lurking
+                    } else {
+                        MonsterState::Dormant
+                    }
+                },
+                MonsterState::Lurking => {
+                    // 30% chance to start hunting, 20% to go dormant, 50% to start wandering
+                    let roll = rand.random_range(0.0..1.0);
+                    if roll < 0.3 {
+                        danger.last_sound_timer.reset();
+                        MonsterState::Hunting
+                    } else if roll < 0.5 {
+                        MonsterState::Dormant
+                    } else {
+                        MonsterState::Wandering
+                    }
+                },
+                MonsterState::Wandering => {
+                    // 20% chance to start hunting, 30% to go lurking, 50% to keep wandering
+                    let roll = rand.random_range(0.0..1.0);
+                    if roll < 0.2 {
+                        danger.last_sound_timer.reset();
+                        MonsterState::Hunting
+                    } else if roll < 0.5 {
+                        MonsterState::Lurking
+                    } else {
+                        MonsterState::Wandering
+                    }
+                },
+                MonsterState::Hunting => {
+                    // after hunting, always go dormant for a while
+                    MonsterState::Dormant
+                }
+            };
+            
+            // set state
+            monster.state = next_state.clone();
+            monster.state_timer = match next_state {
+                MonsterState::Dormant => Timer::from_seconds(15.0, TimerMode::Once),
+                MonsterState::Lurking => Timer::from_seconds(20.0, TimerMode::Once),
+                MonsterState::Wandering => Timer::from_seconds(30.0, TimerMode::Once),
+                MonsterState::Hunting => Timer::from_seconds(15.0, TimerMode::Once),
+            };
+            
+            // reset pathfinding when state changes
+            pathfinding.current_target = None;
+            println!("new state={:?}", monster.state);
+        }
+        
+        // override state in some cases
+        if let Some(player_pos) = player_pos {
+            let distance = monster_transform.translation.distance(player_pos);
+            
+            // if player is very close and monster isn't hunting, switch to hunting
+            if distance < monster.detection_range * 0.5 && monster.state != MonsterState::Hunting {
+                if rand.random_bool(0.75) {  // 75% chance to notice player
+                    monster.state = MonsterState::Hunting;
+                    monster.state_timer = Timer::from_seconds(20.0, TimerMode::Once);
+                    danger.last_sound_timer.reset();
+                    pathfinding.current_target = None;
+                }
+            }
+        }        
+    }
+}
+
+fn move_monster(
+    time: Res<Time>,
+    mut monster_query: Query<(&Monster, &mut Transform, &mut Velocity, &mut MonsterPathfinding), Without<Player>>,
+    player_query: Query<&Transform, With<Player>>,
+) {
+    let mut rand = rand::rng();
+    
+    if let Ok((monster, mut transform, mut velocity, mut pathfinding)) = monster_query.get_single_mut() {
+        pathfinding.wander_target_timer.tick(time.delta());
+        
+        // move based on state
+        match monster.state {
+            MonsterState::Dormant => {
+                velocity.linvel = Vec3::ZERO;
+            },
+            MonsterState::Lurking => {
+                // get a random wander target if we don't have one or timer expired
+                if pathfinding.current_target.is_none() || pathfinding.wander_target_timer.just_finished() {
+                    let range = 30.0;
+                    let random_offset = Vec3::new(
+                        rand.random_range(-range..range),
+                        0.0,
+                        rand.random_range(-range..range)
+                    );
+                    
+                    let base_pos = if let Ok(player_transform) = player_query.get_single() {
+                        player_transform.translation
+                    } else {
+                        transform.translation
+                    };
+                    
+                    pathfinding.current_target = Some(base_pos + random_offset);
+                    pathfinding.wander_target_timer = Timer::from_seconds(10.0, TimerMode::Once);
+                }
+                
+                // move toward target at slow pace
+                if let Some(target) = pathfinding.current_target {
+                    move_towards_target(&mut transform, &mut velocity, target, monster.speed * 0.65);
+                }
+            },
+            MonsterState::Wandering => {
+                if pathfinding.current_target.is_none() || pathfinding.wander_target_timer.just_finished() {
+                    if let Ok(player_transform) = player_query.get_single() {
+                        // choose a random position somewhat close to player
+                        let range = 15.0;
+                        let random_offset = Vec3::new(
+                            rand.random_range(-range..range),
+                            0.0,
+                            rand.random_range(-range..range)
+                        );
+                        
+                        pathfinding.current_target = Some(player_transform.translation + random_offset);
+                        pathfinding.wander_target_timer = Timer::from_seconds(7.0, TimerMode::Once);
+                    }
+                }
+                
+                // move toward target at medium pace
+                if let Some(target) = pathfinding.current_target {
+                    move_towards_target(&mut transform, &mut velocity, target, monster.speed * 0.85);
+                }
+            },
+            MonsterState::Hunting => {
+                // chase the motherfucker
+                if let Ok(player_transform) = player_query.get_single() {
+                    move_towards_target(
+                        &mut transform, 
+                        &mut velocity, 
+                        player_transform.translation, 
+                        monster.speed * 1.1
+                    );
+                }
+            }
+        }
+    }
+}
+
+fn move_towards_target(
+    transform: &mut Transform,
+    velocity: &mut Velocity,
+    target: Vec3,
+    speed: f32
+) {
+    let direction = (target - transform.translation).normalize_or_zero();
+    let direction = Vec3::new(direction.x, 0.0, direction.z).normalize_or_zero();
+    velocity.linvel = direction * speed;
+    
+    if direction.length_squared() > 0.01 {
+        let look_direction = Vec3::new(direction.x, 0.0, direction.z).normalize_or_zero();
+        if look_direction != Vec3::ZERO {
+            let target_rotation = Quat::from_rotation_arc(Vec3::Z, look_direction);
+            transform.rotation = transform.rotation.slerp(target_rotation, 0.1);
+        }
+    }
+}
+
+fn play_monster_sounds(
+    time: Res<Time>,
+    audio: Res<Audio>,
+    audio_assets: Res<AudioAssets>,
+    mut monster_query: Query<(&mut Monster, &Transform), Without<Player>>,
+    player_query: Query<&Transform, With<Player>>,
+) {
+    let mut rand = rand::rng();
+    if let (Ok((mut monster, monster_transform)), Ok(player_transform)) = 
+        (monster_query.get_single_mut(), player_query.get_single()) {
+
+        monster.footstep_timer.tick(time.delta());
+        let distance = monster_transform.translation.distance(player_transform.translation);
+        
+        // play footstep sound if the timer finished
+        if monster.footstep_timer.just_finished() {
+            match monster.state {
+                MonsterState::Hunting => {
+                    monster.footstep_timer = Timer::from_seconds(1.5, TimerMode::Once);
+                },
+                MonsterState::Lurking | MonsterState::Wandering => {
+                    monster.footstep_timer = Timer::from_seconds(
+                        rand.random_range(3.0..7.0),
+                        TimerMode::Once
+                    );
+                },
+                MonsterState::Dormant => {
+                    monster.footstep_timer = Timer::from_seconds(
+                        rand.random_range(10.0..20.0),
+                        TimerMode::Once
+                    );
+                }
+            }
+
+            play_footstep_segment(audio, &audio_assets, distance, &monster.state, monster.footstep_timer.duration().as_secs_f32());
+
+            if monster.state == MonsterState::Hunting && rand.random_bool(0.3) {
+                println!("Monster growl!");
+            }
+        }
+    }
+}
+
+fn play_footstep_segment(
+    audio: Res<Audio>,
+    audio_assets: &Res<AudioAssets>,
+    distance: f32,
+    state: &MonsterState,
+    dur: f32
+) {
+    let base_volume: f32 = match state {
+        MonsterState::Dormant => 0.6,
+        MonsterState::Lurking => 0.65,
+        MonsterState::Wandering => 0.8,
+        MonsterState::Hunting => 1.0,
+    };
+    
+    // adjust volume based on distance (closer = louder)
+    let distance_factor: f32 = 1.0 - (distance / 100.0).clamp(0.0, 1.0);
+    let volume = base_volume * distance_factor;
+    
+    // play only a short segment of the footstep sound
+    // by only playing the last part
+    let mut start_time = 30.0 - dur;
+    // let mut rand = rand::rng();
+    // start_time += rand.random_range(0.0..5.0);
+
+    audio.play(audio_assets.monster_footsteps.clone())
+        .with_volume(Volume::Amplitude(volume as f64))
+        .start_from((start_time as f64).min(27.0))
+        .fade_in(AudioTween::linear(Duration::from_millis(100)))
+        .handle();
+    
+    println!("Monster footstep: State={:?}, Distance={:.2}, Volume={:.2}, Dur={:1}, Start={:1}", 
+        state, distance, volume, dur, (start_time as f64).min(27.0));
+}
\ No newline at end of file