Chivalry
 

One of the best MP games I have played in a long time. Just released their first content update.

13 new maps, 10 new duel arenas, 5 new weapons, 2 new game modes.

...free(and you pay for COD content without blinking)

I've kept returning to this on Steam debating whether to get it.

you should have tried it out last weekend, they had a free weekend and the game was 50% off