WADs in Doom 2, ZANDRONUM
Shotgun Frenzy is a Skulltag modification which combines RTS and FPS, similar to popular mods like Natural Selection. A single player commands their team through a top-down view, building structures and deploying orders, while the rest of the players enter the battlefield and hold off thousands of incoming monsters.
Chagre Sequence is a simple CTF map designed for 8-12 players. There are five routes going through the map. Each one of them is connected to eachother, and all five are shared by both teams. There are plenty of bridge things, so make sure to have co_realactorheight set to 1 (or whatever is the corresponding command in your source port of choice).