If you feel like your life needs more random decapitations and hundreds of people screaming battlecries for absolutely no reason, then you're in luck as Chivalry: Medieval Warfare is free on Steam for this weekend. Simply head on over to Chivalry's Steam page, press the giant green button that says Play Now, and have fun for the next two days!
However, if you've never actually paid any attention to Chivalry and you're now wondering what in the world is it even about, here's the relatively old (but still pretty informative) launch trailer:
And finally, if you find yourself enjoying Chivalry and wish to continue slicing people up long after the weekly promotion has gone away, you can ensure yourself that future at an 80% discount. Whether its worth it or not, that's completely up to you to decide, but for €2 I would say that Chivalry is quite the bargain. Have fun!