recommend me some good coop games

INSURGENCY

Portal 2.

Serious Sam.

Castle Crashers

Divinity Original Sin - very long story and challenging world requires alot of concentration from both players - but if u like RPGs it shouldn't be a problem

What about Resident Evil 5?

Interstellar Marines - it is bare-bones at the moment (pre-alpha) but would be a great investment for the future. What is available now is fun, there is just little content, bugs, and low performance. Development speed has picked up significantly over the past few months, about an update a month with the next one coming mid-December. Awesome community too. Remember: press k for knife.

Me and a mate are having a blast with FarCry 4

Magicka

Splinter Cell: Blacklist. Got some fun with it.

Torchlight 2, Borderlands 2, Left 4 Dead 2, Orcs Must Die 2, F.E.A.R 3.

Swtor

Mount and Blade Warband with the Battletime mod. Epic!

That Lambda Wars Beta is not a bad coop game. Especially the Overrun mode.

No More Room in Hell (it’s free on Steam).

The Red Solstice - basically old school Night of the Dead custom map mod that used to be played a bit before on starcraft & warcraft 3 back in the day. Sadly, however its community is dying or so i heard and games are getting harder to come by which is kind of to be expected from such a unique and niche game. Definitely on my to buy and try with friends co-op kinda game, just need the time and resources. Ultimate survival co-op with up to 8 friends/strangers... what's not to love. Came out middle of this year so still being somewhat developed so new content and fixes still being rolled out.

[I'm really hoping it will catch on and grow into a medium sized community so that it will push the devs to work on it more and add more things hopefully maybe even spawning a new co-op genre revolution/experience. I know L4D2 and Killing Floor and Payday 1/2 has did its part.]

edit: bleh... english not so gut