Mostly I've just gotten the typical cuts and bruises, missing skin from my knees, etc.
My worst "injury" though was last summer during a local Xball tournament. We were tied with another team at four wins each, going into the last match of the game (it was first to 5). It got down to just me in a center can vs. one guy on the other team in the snakem, about 30 feet away. We snap shot each other for a bit, and he finally got a ball on me, right on my mask, but for some reason it hurt a lot more than normal and I tasted blood immediately. The ball somehow went right through the slit on my Profiler and impacted me fully right under the nose, giving me two fat/cut lips and a fairly bad bloody nose.
I immediately got off the field and tore my mask off, yelling for the refs to check his gun. I guess the blood convinced them, so they chrono'd his gun...at almost 320 fps. Thanks to this, they lost the game, we won, and eventually came in 2nd in the tournament.
A little while later...I had already cleaned a little blood off
Inside of my mask