diff --git a/scripts/gui/ranking.gd b/scripts/gui/ranking.gd
index 9cbc17b..8ee792f 100644
--- a/scripts/gui/ranking.gd
+++ b/scripts/gui/ranking.gd
@@ -42,24 +42,27 @@ func more_checkpoint(a: Participant, b: Participant) -> bool:
 	var b_marble = b.get_marble()
 
 	var out: bool
-	if (
-		a_marble.has_finish() and b_marble.has_finish()
-		or a_marble.get_checkpoint_count() == b_marble.get_checkpoint_count()
-	):
+	if a_marble.has_finish() and b_marble.has_finish():
 		out = a.get_rank() < b.get_rank()
 	elif a_marble.has_finish():
 		out = true
 	elif b_marble.has_finish():
 		out = false
 	else:
-		if a_marble.has_explode() and b_marble.has_explode():
+		if (
+			(a_marble.has_explode() or a_marble.has_oob())
+			and (b_marble.has_explode() or b_marble.has_oob())
+		):
 			out = a.get_rank() < b.get_rank()
-		elif a_marble.has_explode():
+		elif a_marble.has_explode() or a_marble.has_oob():
 			out = false
-		elif b_marble.has_explode():
+		elif b_marble.has_explode() or b_marble.has_oob():
 			out = true
 		else:
-			out = a_marble.get_checkpoint_count() > b_marble.get_checkpoint_count()
+			if a_marble.get_checkpoint_count() == b_marble.get_checkpoint_count():
+				out = a.get_rank() < b.get_rank()
+			else:
+				out = a_marble.get_checkpoint_count() > b_marble.get_checkpoint_count()
 	return out
 
 
diff --git a/scripts/main.gd b/scripts/main.gd
index e6f67f2..dbda8a4 100644
--- a/scripts/main.gd
+++ b/scripts/main.gd
@@ -17,6 +17,7 @@ var _current_marble_index := 0
 var _time := 0.0
 var _explosion_enabled := false
 var _race_has_started := false
+var _lower_boundary = null
 
 # Variables used in explosion mode to check
 # if we need to generate another chunk of the race
@@ -105,6 +106,7 @@ func _unhandled_input(event):
 				KEY_R:
 					if _mode == State.MODE_MARBLE:
 						_race.generate_race(!_explosion_enabled)
+						_lower_boundary = get_lowest_piece(_race, true).global_transform.origin.y
 
 				KEY_SPACE:
 					for marble in _marbles:
@@ -157,13 +159,39 @@ func get_highest_piece() -> Piece:
 	var pieces = _race.get_children()
 	if len(pieces) == 0:
 		return null
-	var highest_piece = pieces[0]
+	var highest_piece = null
 	for piece in pieces:
-		if piece.position.y > highest_piece.position.y:
+		if not piece is Piece:
+			continue
+		if highest_piece == null:
+			highest_piece = piece
+		elif piece.position.y > highest_piece.position.y:
 			highest_piece = piece
 	return highest_piece
 
 
+func get_lowest_piece(piece_or_race, recursive: bool = false) -> Piece:
+	var pieces = piece_or_race.get_children()
+	if len(pieces) == 0:
+		return null
+
+	# Find the lower piece from children of the current node3d
+	var lowest_piece = null
+	for piece in pieces:
+		if not piece is Piece:
+			continue
+		if lowest_piece == null:
+			lowest_piece = piece
+		elif piece.position.y < lowest_piece.position.y:
+			lowest_piece = piece
+
+	if recursive:
+		var child_lowest_piece = get_lowest_piece(lowest_piece)
+		if child_lowest_piece != null:
+			lowest_piece = child_lowest_piece
+	return lowest_piece
+
+
 # Replace cameras with a new one
 func replace_camera(new_camera, old_cameras) -> void:
 	# Ensure old cameras are removed from the current scene
@@ -212,11 +240,12 @@ func set_mode(mode):
 		# If no marbles exist
 		if start_a_new_race:
 			_podium.hide()
-			
+
 			await Fade.fade_out(1, Color.BLACK, "Diamond", false, false).finished
 
 			_explosion_enabled = SettingsManager.get_value(&"marbles", &"explosion_enabled") as bool
 			_race.generate_race(!_explosion_enabled)
+			_lower_boundary = get_lowest_piece(_race, true).global_transform.origin.y
 
 			_overlay.reset()
 			reset_position()
@@ -316,6 +345,7 @@ func _process(delta):
 				if lap_count > _old_lap_count:
 					# Generate a chunk
 					_race.generate_chunk()
+					_lower_boundary = get_lowest_piece(_race, true).global_transform.origin.y
 					_old_lap_count = lap_count
 	else:
 		_panel_timer.hide()
@@ -344,6 +374,16 @@ func _process(delta):
 				_podium.set_second(_ranking._second_marble)
 				_podium.set_third(_ranking._third_marble)
 
+	# Check if some marbles are out of bound
+	if _race_has_started and _lower_boundary != null:
+		for marble in _marbles:
+			if (
+				marble.visible
+				and marble._state == Marble.State.ROLL
+				and marble.global_transform.origin.y + 100 < _lower_boundary
+			):
+				marble.out_of_bound()
+
 
 # Handle victory conditions on explosion mode
 func explosion_victory(_last_marble: Marble) -> bool:
diff --git a/scripts/marble.gd b/scripts/marble.gd
index bee4eef..e17f55f 100644
--- a/scripts/marble.gd
+++ b/scripts/marble.gd
@@ -86,9 +86,6 @@ func _process(_delta: float) -> void:
 	_name.global_transform.origin = offset
 	_score.global_transform.origin = offset + Vector3(-0.4, -0.2, 0)
 
-	if global_transform.origin.y < -10000:
-		out_of_bound()
-
 
 func reset() -> void:
 	_start()