Are there any fps that are blood free

robots the video game is like a fps with a bunch of guns and a light saber, and yes there is no blood, its more clean than you can imagine. There is also a game called Cube 2: Saubraten. It has a feature were you can turn the blood on and off. Its Open Source, so it free too! I believe that you can also do the same in a game called Assault Cube, which is based off the Cube 2 engine.