Nope, I meant this Doom, whose original source code is here on GitHub.
I'm surprised you've not got OpenRCT2 to work - I'm fairly sure it's in most default repos.

You do need to have a full copy of RollerCoaster Tycoon 2 as it uses data / assets from the original game.
I would happily link you to Unreal Tournament, but it's no longer for sale anywhere as far as I'm aware.