This game is pretty good and is free.
It's a free arena FPS that uses parkour movement as its unique gimmick. It's also got the conventional arena FPS tropes of countless maps, game modes, and mutators to spice up the gameplay.

The only downside is that it's criminally underplayed but is continually being developed with a Steam release coming soon.

https://www.youtube.com/watch?v=Zf3XN553RuA