It's Zeno Clash, and it runs on the Source engine.
I pre-ordered it during the 75% discount weekend for like 8 dollars because it looked interesting.
Combat is pretty fun, one of the best first person fighting games i've played (including Dark Messiah, which is rather simplistic in comparison tbh. There are more combo's etc possible in Zeno, and the artistic style flowed into some combat moves as well, like people standing on their head to kick you breakdance-style, stuff like that).
I had little clue as to what to expect going into the game though, there are some arena-type area's, but also some locations where you have to advance across the map. Not a lot of freedom here, but a fighting game doesnt really need it.
The art style is fresh, the gameplay pretty cool, and it's not to expensive, so if you need something new this one definitely a recommendation.