private void OnTriggerEnter2D(Collider2D other)
 {
     if (other.GetComponent <CharacterMovement>() != null)
     {
         soundPlayer.PlayExplosionSound();
         scoreTracker.AddBomb();
         Disappear();
     }
     else if (other.GetComponentInParent <CollectAllPower>() != null)
     {
         // sound played by collectallpower script
         Disappear();
     }
 }