Mechwarrior Online (free to play)
Quake Champions (free to play)
Quake Live
Elder Scrolls Online
Rising Storm 2
Tabletop Simulator
Elite Dangerous
EVE Online (free to play)
Final Fantasy XI (i have a private server for this)
Final Fantasy XIV
Garry's Mod
Golf with your friends
Guild Wars 2 (free to play)
Hunt: Showdown (really want to play more of this)
Killing Floor
Killing Floor 2
League of Legends
Battlefield 1
Battlefield 4
Battlefield 5
Chivalry: Medieval Warfare
Counter-strike: Source
Diablo 3
Destiny 2
Insurgency: Sandstorm
For Honor

Coop:
Warhammer: Vermintide
Warhammer: Vermintide 2
Crackdown 3
Dark Souls
Broforce
Divinity: Original Sin
Far Cry 5
Resident Evil 5
Resident Evil 6
Shadow Warrior 2
Sniper Elite V2
The Escapists 2
Lost Planet 2
Monster Hunter: World
Starbound
Stardew Valley
Tower Unite
Rainbow Six Vegas 2
Trackmania 2 canyon
Trackmania 2 stadium
Warframe