demon_fastshot.bin - Super fast shots from your cannon. Makes the game pretty easy, but it's fun to plow through the demons with the fast shots, they have no chance!
demon_nofireback.bin - The enemies never fire back at you in this version.
demon_alwayssmallenemies.bin - The enemies are always the small "ball" type that you see in the final wave. Much harder to hit.
demon_startwith6lives.bin - You start the game off with 6 lives instead of 3.