Clash at Demonhead/Route 20

Description
This is a very short route. Assuming that you've entered from the right side, advance to the left. Eliminate any looping enemies, and small bouncing enemies that you encounter. When you're closer to the center of the route, a set of heat seeking missiles will fly on to the screen. Shoot them or duck down low to avoid them. Then remove any remaining enemies that approach you on your way to the exit.