Right off the bat we're doing a trench run and shooting down alien scum. I've heard others say that killing these buggers is difficult but I found them to be well telegraphed; there's three levels top, middle, and bottom and each has a very specific animation. After exiting the trench you're in open space making it much easier since you don't have walls to avoid. The third Androids style level is the most difficult but as long as you get an invincibility power-up you've got it made because they spawn like crazy. Boss level is super easy, and goes down within 10 seconds. Go through the loop again, and you've got yourself a simple game. Fine!