Call of Duty - Call of Duty is a first-person and third-person shooter series by Infinity Ward.
Roblox - Reimagining the way people come together.
Quake - Quake is a series of first-person shooter video games released by id Software.
Blockland - Blockland is a non-competitive multiplayer sandbox-style construction game. It's kind of like playing with legos on the internet.
Xonotic - Xonotic is a free (GPL), fast-paced first-person shooter that works on Windows, OS X and Linux.
Garry’s Mod - Garry’s Mod is Funny, Sandbox, Co-op, Building, FPS, Action, Single and Multiplayer video game created by Facepunch and published by Valve.