Team Raycast released a new mod: Splitwolf 1.0. This release gives you the ability to play two-player co-op splitscreen with another player. Next to that, this new release features various new game mods, as well as new features such as MG42's and armored vehicles. Which you can all play in the classic Wolf3D maps! You can download the mod HERE. Its ModDb page can be found HERE. There's also the possibility to discuss this mod at its thread over at the DHW forum, which you can find right HERE.