Zandronum

Zandronum is an open-source multiplayer source port forked off from the most recent development of the source port Skulltag. Created by the former Skulltag development team, they forked off into their own port due to conflicts with Skulltag's creator, Brad "Carnevil" Carney. Like Skulltag, Zandronum is based on ZDoom and on the GZDoom renderer.