sum fixes

Scripts/BasicEnemy.cs

@@ -0,0 +1,20 @@
+using Godot;
+
+public partial class BasicEnemy : Node3D
+{
+   protected GameManager _gameManager;
+
+   public override void _Ready()
+   {
+      _gameManager = GetTree().Root.GetNode<GameManager>("Main/GameManager");
+   }
+
+   public void OnEnemyHit(Node3D node)
+   {
+      QueueFree();
+      if (_gameManager.CheckAllEnemiesDefeated())
+      {
+         _gameManager.OnAllEnemiesDefeated();
+      }
+   }
+}