Günther

Günther earned his name because of his ..ehm... "foul appearance" one might put it... ok, his rather extremely large penis! - there you have it.
It's way too big to be kept emprisoned behind clothes, and he always has a toothless, dirty smile on his face as he carries it around.
Fortunately it has also made him a cruel bloodbowl player - especially when it comes to fouling (in the time where fouling earned SPP, red.). And with his devotion to spiky body piercings it turned out very lethal to have him slash his "thing" at prone players.
Thus he was the top league killer at the time of his (and his team's) retirement.