A small single player/multiplayer map I decided to make for the Brutal Doom related mod "Schism", however this map can run with Brutal Doom v21 as well (may get some issues with Schism I don't care to deal with at the moment). Enjoy!
To run, I recommend the latest Zandronum version (3.1) to run it (it is required for latest build of Schism). If it is too quirky for ya, Zandronum 3.0 should be fine too. GZDoom should work too if using Brutal Doom v21. Just select MarbleTerror.wad along with either Brutalv21.pk3 or the latest Schism (I was using their BD_Schism_092C.pk3 to play it) and drag em to the Zandronum/Gzdoom .exe. Last Thing, this game requires Doom II .wad to play (freedoom may work too but may look like ass!). If anyone want's to know more about the mod Schism I may make a discord link in the comment section later (Gotta ask the design lead first if that is alright with him).
Map itself - LordADHD
additional DECORATE code - Got from Schism but also got from Brutal Doom by SGT_MARK_IV (some of that code looks to be from Project Brutality also). Modified by LordADHD.