Magicka

Let's enter the indie games genre. This game is just awesome! You are a wizard that have to save the world from a dangerous wizard.  And you get thrown into a strange world, where you can destroy anything or anyone friend or foe. It's a nice game!

You can combine several elements to make new attacks, you unlock spells by finding books and proceeding through the game. This is an excellent co/op game, but beware you can destroy your friend easily if you fire the spells in the wrong direction!
But that's just some of the charm with this game it's so free, and if you are from the scandinavia area you can hear that the words they are speaking sounds alot like swedish. Just a little fun fact.

But this game is super funny and there are several downloable contents for this game so it's like playing a new game. But yeah this is quite famous already but the ones who havent played it should play it now!

The rating is a clear 9/10 it's really funny.

Check it out on the steam website:
http://store.steampowered.com/app/42910/