Wow I cant Believe Siege has not been included yet !!!
So much fun to be had especially if you play with a team you know, its also a very social game as well I have met plenty of peeps through playing the game.
Have a bunch of little clips on my youtube channel
https://www.youtube.com/user/kill4virus/videos
I tend to get a clip per night of something that i think is worth uploading (but I try not to lol)
I am amazed how much it has kept me entertained and I have not got bored of it yet,
There is no 29 month long grind to unlock all the weapons and operators it can be done in a month or so (playing evenings). Its simple mechanics with alot of possibilities, the recipe for some of the best games. Its not quite like the video below, that was me going a bit mental
its is generally headshot = dead game
Also this but you may not forgive me for this one, check out Factorio, This game is pure addiction, They have just completely rewritten the multiplayer after SHOCK HORROR a game developer admitted they should of listened to the community and made a mistake.
https://www.factorio.com/blog/post/fff-147 For this alone i have alot of respect for them, and if prison architect and minecraft ever interested you, I would highly recommend this game.
P.s. If you enjoy eating sleeping defecating and interacting with outer humans you may want to avoid this game, Oh and read the reviews They are quite amusing.
http://store.steampowered.com/app/427520/
p.s. Don't bother watching the video to get a feel of the game it doesn't work like that.