diff --git a/engine/src/modules/ai/wild_creature_ai.gd b/engine/src/modules/ai/wild_creature_ai.gd
index 8ce7027a..501e5697 100644
--- a/engine/src/modules/ai/wild_creature_ai.gd
+++ b/engine/src/modules/ai/wild_creature_ai.gd
@@ -1,2 +1,238 @@
 class_name WildCreatureAI
 extends RefCounted
+## Governs wild creature behavior each turn.
+## Wild creatures (owner == -1) guard their home NPC building (lair), attack player
+## units within detection radius, and roam within a leash radius.
+## Called by TurnManager during the wild creatures phase.
+
+const UnitScript = preload("res://engine/src/entities/unit.gd")
+const HexUtilsScript = preload("res://engine/src/map/hex_utils.gd")
+const PathfinderScript = preload("res://engine/src/map/pathfinder.gd")
+const UnitManagerScript = preload("res://engine/src/modules/management/unit_manager.gd")
+
+const DEFAULT_DETECTION_RADIUS: int = 4
+const DEFAULT_LEASH_RADIUS: int = 5
+const ROAM_CHANCE: int = 40
+
+var _rng: RandomNumberGenerator = RandomNumberGenerator.new()
+var _unit_manager: RefCounted
+
+
+func _init(unit_manager: RefCounted) -> void:
+	_unit_manager = unit_manager
+	_rng.randomize()
+
+
+func process_wild_turn(game_map: RefCounted) -> void:
+	var primary_layer: Dictionary = GameState.get_primary_layer()
+	if primary_layer.is_empty():
+		return
+
+	var wild_units: Array = []
+	for unit_ref: Variant in primary_layer.get("units", []):
+		if unit_ref is UnitScript and unit_ref.owner == -1 and unit_ref.is_alive():
+			wild_units.append(unit_ref)
+
+	var wilds_cfg: Dictionary = _get_wilds_config()
+	var detection_radius: int = wilds_cfg.get("detection_radius", DEFAULT_DETECTION_RADIUS)
+	var leash_radius: int = wilds_cfg.get("roaming_leash_radius", DEFAULT_LEASH_RADIUS)
+
+	for unit: RefCounted in wild_units:
+		unit.refresh_turn()
+		_act(unit, game_map, detection_radius, leash_radius)
+
+
+func spawn_initial_creatures(game_map: RefCounted) -> void:
+	## Spawn one tier-1 creature at every lair NPC building.
+	var wilds_cfg: Dictionary = _get_wilds_config()
+	var lair_types: Array = wilds_cfg.get("lair_types", [])
+	var primary_layer: Dictionary = GameState.get_primary_layer()
+	if primary_layer.is_empty():
+		return
+
+	for b: Variant in GameState.npc_buildings:
+		var type_id: String = b.type_id
+		# Skip non-lair buildings (villages, ruins)
+		if type_id == "village" or type_id == "ruin":
+			continue
+
+		var tier1_pool: Array = _get_tier_pool(type_id, "tier_1", lair_types)
+		if tier1_pool.is_empty():
+			continue
+
+		var unit_type_id: String = tier1_pool[_rng.randi() % tier1_pool.size()]
+		var unit_data: Dictionary = DataLoader.get_unit(unit_type_id)
+		if unit_data.is_empty():
+			continue
+
+		var unit: RefCounted = UnitScript.new()
+		unit.id = "wild_%d" % _rng.randi()
+		unit.type_id = unit_type_id
+		unit.owner = -1
+		unit.position = b.position
+		unit.max_hp = unit_data.get("hp", 8)
+		unit.hp = unit.max_hp
+		unit.movement_remaining = unit_data.get("movement", 2)
+		unit.has_attacked = false
+
+		primary_layer.get("units", []).append(unit)
+		EventBus.wild_creature_spawned.emit(unit, b.position)
+
+
+func _act(
+	unit: RefCounted,
+	game_map: RefCounted,
+	detection_radius: int,
+	leash_radius: int,
+) -> void:
+	if unit.movement_remaining <= 0:
+		return
+
+	var home_pos: Vector2i = _find_nearest_lair(unit.position, leash_radius + 2)
+	var target_pos: Variant = _find_attack_target(unit, detection_radius)
+
+	if target_pos != null:
+		_move_toward(unit, target_pos, game_map)
+	elif _is_outside_leash(unit.position, home_pos, leash_radius):
+		_move_toward(unit, home_pos, game_map)
+	elif _rng.randi_range(1, 100) <= ROAM_CHANCE:
+		_roam(unit, home_pos, game_map, leash_radius)
+
+
+func _find_attack_target(
+	unit: RefCounted,
+	detection_radius: int,
+) -> Variant:
+	var primary_layer: Dictionary = GameState.get_primary_layer()
+	var candidates: Array[Dictionary] = []
+
+	for other: Variant in primary_layer.get("units", []):
+		if not other is UnitScript:
+			continue
+		if other.owner < 0:
+			continue
+		var dist: int = HexUtilsScript.hex_distance(unit.position, other.position)
+		if dist <= detection_radius:
+			candidates.append({"pos": other.position, "dist": dist})
+
+	if candidates.is_empty():
+		return null
+
+	candidates.sort_custom(func(a: Dictionary, b: Dictionary) -> bool:
+		return a["dist"] < b["dist"]
+	)
+	return candidates[0]["pos"]
+
+
+func _find_nearest_lair(from_pos: Vector2i, search_radius: int) -> Vector2i:
+	## Find nearest lair NPC building within search_radius via GameState.
+	var best_pos: Vector2i = from_pos
+	var best_dist: int = 999999
+
+	for b: Variant in GameState.npc_buildings:
+		if b.type_id == "village" or b.type_id == "ruin":
+			continue
+		var dist: int = HexUtilsScript.hex_distance(from_pos, b.position)
+		if dist <= search_radius and dist < best_dist:
+			best_dist = dist
+			best_pos = b.position
+
+	return best_pos
+
+
+func _is_outside_leash(
+	unit_pos: Vector2i, home_pos: Vector2i, leash_radius: int
+) -> bool:
+	return HexUtilsScript.hex_distance(unit_pos, home_pos) > leash_radius
+
+
+func _move_toward(
+	unit: RefCounted,
+	target: Vector2i,
+	game_map: RefCounted,
+) -> void:
+	var pathfinder: RefCounted = PathfinderScript.new(game_map)
+	var path: Array[Vector2i] = pathfinder.find_path(
+		unit.position, target, unit.movement_remaining, unit.is_flying()
+	)
+
+	if path.size() < 2:
+		return
+
+	var next_pos: Vector2i = path[1]
+
+	var units_there: Array = _unit_manager.get_units_at(next_pos)
+	for other: Variant in units_there:
+		if other is UnitScript and other.owner >= 0:
+			return
+
+	var from_pos: Vector2i = unit.position
+	var tile: Variant = game_map.get_tile(next_pos)
+	if tile == null:
+		return
+
+	var cost: int = tile.get_movement_cost()
+	if unit.is_flying():
+		cost = 1
+
+	if unit.movement_remaining < cost:
+		return
+
+	unit.movement_remaining -= cost
+	unit.position = next_pos
+	EventBus.unit_moved.emit(unit, from_pos, next_pos)
+
+
+func _roam(
+	unit: RefCounted,
+	home_pos: Vector2i,
+	game_map: RefCounted,
+	leash_radius: int,
+) -> void:
+	var neighbors: Array[Vector2i] = HexUtilsScript.get_neighbors(unit.position)
+	var valid: Array[Vector2i] = []
+
+	for neighbor: Vector2i in neighbors:
+		if not game_map.is_valid_position(neighbor):
+			continue
+		var tile: Variant = game_map.get_tile(neighbor)
+		if tile == null or tile.is_water():
+			continue
+		if HexUtilsScript.hex_distance(neighbor, home_pos) > leash_radius:
+			continue
+		var units_there: Array = _unit_manager.get_units_at(neighbor)
+		var has_player_unit: bool = false
+		for u: Variant in units_there:
+			if u is UnitScript and u.owner >= 0:
+				has_player_unit = true
+				break
+		if not has_player_unit:
+			valid.append(neighbor)
+
+	if valid.is_empty():
+		return
+
+	var dest: Vector2i = valid[_rng.randi() % valid.size()]
+	var from_pos: Vector2i = unit.position
+	unit.movement_remaining -= 1
+	unit.position = dest
+	EventBus.unit_moved.emit(unit, from_pos, dest)
+
+
+func _get_tier_pool(lair_type_id: String, tier: String, lair_types: Array) -> Array:
+	for lt: Dictionary in lair_types:
+		if lt.get("id", "") == lair_type_id:
+			var spawn_pool: Dictionary = lt.get("spawn_pool", {})
+			return spawn_pool.get(tier, [])
+	return []
+
+
+func _get_wilds_config() -> Dictionary:
+	var data: Dictionary = DataLoader.get_wilds_config()
+	if not data.is_empty():
+		return data
+	return {
+		"detection_radius": DEFAULT_DETECTION_RADIUS,
+		"roaming_leash_radius": DEFAULT_LEASH_RADIUS,
+		"lair_types": [],
+	}