I really don't know of many FPS games which are for VR and have PVP/Co-Op Multiplayer. So that said, here's the question...what are they??? Thx for any suggestions!
COOP: 1) Dead Effect 2 VR I think, I've never actually tried to play it in COOP mode but it is listed as an option. 2) Dead and Buried (free, boring and looks like a cell phone game, but it is free).
Competitive: 1) Onward. 2) Pavlov (haven't tried it). 3) Dead and Buried (has both COOP and competitive modes).
NOTE: it is on the Gear VR store. You won't find it on the Rift store yet, but it is planned for launch and to my knowledge if you download it from here it will detect Rift on startup (since 2013).
This is what a furball can look like. Here is a group-based, guild-driven, naturally occurring sector conflict. Imagine that in VR. It's good.