This Remix shows a solution for the problem that clones of Bullet could not destroy clones of Enemy airplane. Two key points: 1. Use Sensing "Touching <a color>" instead of "Touching <a sprite>". 2. Add a parallel "I Start as a Clone" block and place the above Sensing there. Leave the motion animation with the other "I Start as a Clone" block. This way moving and sensing can happen at the same time without interfering with each other.