diff --git a/scripts/Contents/Panels/MakeFeed.gd b/scripts/Contents/Panels/MakeFeed.gd
index c26cb26..99a3212 100644
--- a/scripts/Contents/Panels/MakeFeed.gd
+++ b/scripts/Contents/Panels/MakeFeed.gd
@@ -50,7 +50,11 @@ func updateValue():
 	countLabel.text = str(UIState.player.fields[FieldStore.Entity.FEED_COUNT_CAN_MADE] - selectedCount)
 	needBB.count = refreshNeedBaseballCount
 func finish():
-	WorldManager.rootNode.spawnWave()
+	var center = Vector2.ZERO
+	for player in EntityBase.getPlayers():
+		center += player.position
+	center /= len(EntityBase.getPlayers())
+	WorldManager.rootNode.spawnWave(center)
 	UIState.closeCurrentPanel()
 func regenerateCards():
 	updateValue()
diff --git a/scripts/Contents/Panels/Starter.gd b/scripts/Contents/Panels/Starter.gd
index 7622b7f..157174e 100644
--- a/scripts/Contents/Panels/Starter.gd
+++ b/scripts/Contents/Panels/Starter.gd
@@ -64,7 +64,7 @@ func startSingleplayerGame():
 	MultiplayerState.isMultiplayer = false
 	MultiplayerState.playerName = playerNameInput.text
 	EntityBase.generatePlayer(playerNameInput.text)
-	WorldManager.rootNode.spawnWave()
+	WorldManager.rootNode.spawnWave(Vector2.ZERO)
 	UIState.closeCurrentPanel()
 
 func _ready():
diff --git a/scripts/Contents/Wave.gd b/scripts/Contents/Wave.gd
index d73b394..cc6b255 100644
--- a/scripts/Contents/Wave.gd
+++ b/scripts/Contents/Wave.gd
@@ -82,13 +82,13 @@ static func entityCountOf(wave: Wave) -> int:
 		elif !hasBoss():
 			return randi_range(ceil(wave.minCount), floor(wave.maxCount * (1 + GameRule.entityCountBoostPerWave * current)))
 	return 0
-static func spawn() -> Array:
+static func spawn(center: Vector2) -> Array:
 	var result: Array = []
 	for i in range(len(data)):
 		var wave: Wave = data[i]
 		for j in range(entityCountOf(wave)):
 			var currentWave = wave.duplicate()
-			currentWave.entityPosition = MathTool.randv2_range(500)
+			currentWave.entityPosition = MathTool.randv2_range(500) + center
 			result.append(currentWave)
 	return result
 static func next(waves: Array):
diff --git a/scripts/Statemachine/EntityBase.gd b/scripts/Statemachine/EntityBase.gd
index 547bcda..05c4b93 100644
--- a/scripts/Statemachine/EntityBase.gd
+++ b/scripts/Statemachine/EntityBase.gd
@@ -466,7 +466,7 @@ func kill():
 	pass
 
 static func findPlayer(playerName: String) -> EntityBase:
-	for i in WorldManager.tree.get_nodes_in_group("players"):
+	for i in getPlayers():
 		if i.displayName == playerName:
 			return i
 	return null
@@ -493,5 +493,15 @@ static func generate(
 	if addToWorld:
 		WorldManager.rootNode.spawn(instance)
 	return instance
-static func getMobs():
-	return WorldManager.tree.get_nodes_in_group("mobs")
+static func getMobs() -> Array[EntityBase]:
+	var result: Array[EntityBase] = []
+	for entity in WorldManager.tree.get_nodes_in_group("mobs"):
+		if entity:
+			result.append(entity)
+	return result
+static func getPlayers() -> Array[EntityBase]:
+	var result: Array[EntityBase] = []
+	for entity in WorldManager.tree.get_nodes_in_group("players"):
+		if entity:
+			result.append(entity)
+	return result
diff --git a/scripts/Tools/Managers/WorldManager.gd b/scripts/Tools/Managers/WorldManager.gd
index ea0755b..918b887 100644
--- a/scripts/Tools/Managers/WorldManager.gd
+++ b/scripts/Tools/Managers/WorldManager.gd
@@ -19,16 +19,16 @@ func _physics_process(delta):
 		UIState.setPanel("MakeFeed")
 
 @rpc("authority")
-func nextWave(waves: Array):
+func doNextWave(waves: Array):
 	Wave.next(waves)
 
 func canNextWave():
 	return len(EntityBase.getMobs()) == 0 and len(ItemDropped.getDropsCanCollet()) == 0
-func spawnWave():
-	var waves = Wave.spawn()
-	nextWave(waves)
+func spawnWave(center: Vector2):
+	var waves = Wave.spawn(center)
+	doNextWave(waves)
 	if MultiplayerState.isMultiplayer and multiplayer.is_server():
-		nextWave.rpc(waves)
+		doNextWave.rpc(waves)
 func spawn(node: Node):
 	if MultiplayerState.isMultiplayer:
 		if multiplayer.is_server():