This is actually pretty easy if you know the trick. Phase 1: Don't move around on the screen, this makes it 10 times harder. Just stay on the right side of the screen and dodge those two lasers, and let your missles finish him. Phase 2: Save a lv 3 super bomb, and you can completely skip the most difficult phase 2. Phase 3: It's an easy one. Just stay on the right side of the screen, and nothing will hit you.
