This isn't really a proper Hellagem, but I figured I'd offer you a crumb from the Game Boy Advance game I'm working on. I threw this music together very quickly.
The game will involve this marshmallow man jumping around a young boy's gums and attempting to kill all of the teeth in his mouth. When you kill them all with your marshmallow gun, you win. Tooth decay, yay!
For the full effect, let it loop over and over until you are driven mad.