New TowerFall Expansion, "Dark World", Adds Four Player Co-op
TowerFall Ascension, one of the forerunners of the couch multiplayer renaissance, also contains a slightly lesser known two player co-op "Quest" mode. From my experience with the mode, you and a friend alternate between killing monsters and wondering how your compatriot managed to lodge an arrow directly into your skull. Having fully completed the campaign, I can say with some authority that it is a simultaneously fantastic and infuriating addition to the game.