Heretic is a classic first person shooter created by Raven software released on 21-12-1994. It is based off the Doom engine by ID Software. Raven released the source to Heretic on 11-01-1999. dsHeretic is a port of this game to the Nintendo DS. Changes:

Added touch controls for switching weapons, using inventory, and flying up and down.

Added optional music support.

Smoothed out touch screen look a little.

Slowed down the framerate on the automap so it is more reasonable to leave it on all the time.

http://heretic.drunkencoders.com/