While arguably associated more with PvP games, the PC ... Steam, but they also exist and there are some great titles out there. Co-op games that focus on PvP will be largely ignored. Countr-Strike ...
As someone who usually focuses on single-player games, I must admit Steam offers some incredible ... Well, Helldivers 2 is the perfect way to go about that. It's fast-paced, loud, and bloody.