Games that use WAD files or Doom formats or unofficially build on idtech1:   Mars 3D uses MAD and very close to WAD 3D Hero Tao   A.D. Cop - uses GAD very close to WAD A.D. Cop: Overseas Mission Amulets and Armor   Tank Wars - not a 3d game but 2d and uses WAD as container   Birthright: The Gorgon's Alliance - 3d game just founded it uses WAD and maps can be loaded in gzdoom uses same doom map format   Rise of the Triad B