diff --git a/scenes/player.tscn b/scenes/player.tscn
index 68faebe..af9bfa6 100644
--- a/scenes/player.tscn
+++ b/scenes/player.tscn
@@ -11,6 +11,8 @@ radius = 0.35
 height = 1.6
 
 [node name="Player" type="CharacterBody3D"]
+collision_layer = 2
+collision_mask = 1
 script = ExtResource("1_player")
 
 [node name="CollisionShape3D" type="CollisionShape3D" parent="."]
diff --git a/scenes/server_player.tscn b/scenes/server_player.tscn
index cbd6858..2136920 100644
--- a/scenes/server_player.tscn
+++ b/scenes/server_player.tscn
@@ -7,6 +7,8 @@ radius = 0.35
 height = 1.6
 
 [node name="Player" type="CharacterBody3D"]
+collision_layer = 2
+collision_mask = 1
 script = ExtResource("1")
 
 [node name="CollisionShape3D" type="CollisionShape3D" parent="."]
diff --git a/scripts/player.gd b/scripts/player.gd
index cefcb2e..eb78528 100644
--- a/scripts/player.gd
+++ b/scripts/player.gd
@@ -26,6 +26,7 @@ const MOUSE_SENSITIVITY: float = 0.003
 
 var _input_direction := Vector2.ZERO
 var _camera_pitch: float = -0.12
+var _spawn_position: Vector3 = Vector3(0, 1.5, 0)
 
 ## Vertical offset applied to the assembled avatar so its feet (origin y=0)
 ## line up with the bottom of the player's collision capsule.
@@ -69,6 +70,7 @@ func _ready() -> void:
 	else:
 		push_warning("player.gd: no PlayerSpawn marker found; spawning at origin")
 		global_position = Vector3(0, 1.0, 0)
+	_spawn_position = global_position
 
 	# The spring arm must not collide with the player's own capsule (they're
 	# on the same layer), or the camera gets yanked right up against the
@@ -192,6 +194,11 @@ func _physics_process(delta: float) -> void:
 
 	move_and_slide()
 
+	# Safety net -- never fall forever if something goes wrong.
+	if global_position.y < -10.0:
+		global_position = _spawn_position
+		velocity = Vector3.ZERO
+
 	net_input = {
 		"move_x": direction.x, "move_z": direction.z,
 		"jump": jumped, "look_yaw": rotation.y,
diff --git a/scripts/player_spawner.gd b/scripts/player_spawner.gd
index 104b6ff..f574cd9 100644
--- a/scripts/player_spawner.gd
+++ b/scripts/player_spawner.gd
@@ -14,6 +14,10 @@ const GRAVITY := 9.8
 
 var peer_id: int = -1
 
+## Where the server spawned this player (set by server.gd). Used as the
+## respawn point if the player somehow ends up below the world.
+var spawn_position: Vector3 = Vector3(0, 1.5, 0)
+
 ## Highest input seq applied authoritatively so far (echoed in snapshots so
 ## the client can drop acked inputs and replay the rest).
 var last_applied_seq: int = 0
@@ -38,6 +42,13 @@ func _physics_process(delta: float) -> void:
 
 	rotation.y = _look_yaw
 
+	# Safety net: if a player ends up below the world (physics shove, tunnel
+	# through the floor), put them back on their spawn instead of falling
+	# forever.
+	if global_position.y < -10.0:
+		global_position = spawn_position
+		velocity = Vector3.ZERO
+
 
 func _integrate(move_x: float, move_z: float, jump: bool, delta: float) -> void:
 	if not is_on_floor():
diff --git a/scripts/server.gd b/scripts/server.gd
index 5850b91..2061ce1 100644
--- a/scripts/server.gd
+++ b/scripts/server.gd
@@ -30,6 +30,9 @@ var status_file_path: String = ""
 var players: Dictionary = {}
 var tick: int = 0
 var is_running: bool = false
+## Monotonic count of joins ever -- drives spawn spread so two players never
+## land on the same spot (which used to shove one through the floor).
+var _join_count: int = 0
 
 var _player_scene: PackedScene = preload("res://scenes/server_player.tscn")
 var _level_scene: PackedScene = preload("res://scenes/worlds/test_level.tscn")
@@ -65,6 +68,16 @@ func _ready() -> void:
 	print("[Server] world=%s listening on ENet %d (%d Hz)" % [world_id, port, PHYSICS_HZ])
 
 
+## A spawn point offset from the level's marker so joins don't stack. Golden-
+## angle spiral: evenly spread, never exactly repeats, grows slowly outward.
+func _spawn_for(index: int) -> Vector3:
+	if index == 0:
+		return _spawn_point
+	var angle := index * 2.399963  # golden angle (radians)
+	var radius := 0.9 + 0.25 * float(index)
+	return _spawn_point + Vector3(cos(angle) * radius, 0.0, sin(angle) * radius)
+
+
 func _parse_args() -> void:
 	var args := OS.get_cmdline_user_args()
 	var i := 0
@@ -127,7 +140,10 @@ func _on_peer_connected(peer_id: int) -> void:
 	player.name = "Player_%d" % peer_id
 	player.peer_id = peer_id
 	add_child(player)
-	player.global_position = _spawn_point
+	var spawn := _spawn_for(_join_count)
+	_join_count += 1
+	player.global_position = spawn
+	player.spawn_position = spawn
 	players[peer_id] = player
 	print("[Server] peer %d joined (%d players)" % [peer_id, players.size()])
 	_write_status()