Skulltag

Skulltag is a source port by Brad "Carnevil" Carney based on ZDoom.

Features

 * Supports most ZDoom features.
 * Client/server architecture multiplayer.
 * Customizable, dynamic bots.
 * New weapons, items, and monsters.
 * Medals to award achievements during multiplayer.
 * New multiplayer modes, including CTF, Last Man Standing, Instagib, and more.