Left 4 Dead 2, is a good choice if your looking for a zombie game with some workshop content to mod it up, kill zombies as an anime girl, why not?

Not for the faint hearted, however Rust is quite an enjoyable open world survival game despite the naked humanoids running around with rocks.

Insurgency is a first person shooter with team based multiplayer and co-op missions. Interesting gameplay and quite an enjoyable game.

Despite being the original counter-strike, it still maintains what made it so popular, whilst the community is small.. it has not died yet!

A very good choice as an alternative to LoL or Smite when wanting to play a MOBA as a break from CS!

One of the best Counter-Strikes in the series, A very good choice to play other than Counter-Strike:GO while still being similar but still different.

A strange clone of Super Smash Bro's, however it was just as if not more fun than SMB. Requires a Controller!

Counter-Strike:GO, is a fun and addictive team-based 5v5 shooter, with multiple gamemodes and community made content. Definately pick it up!

Garrysmod is a good pickup for anyone looking to have some fun and laughs, There are plenty of different gamemodes or make your own with lua code.