Okay, I know it's a tad ambiguous...and we'll throw in the NFL here, too...but there have been some mean one's. Remember, there are no wrong answer's here:
And you don't have to seperate the league's here:
NFL: Mike Singletarry--those eyes. The Baylor Bear was a beast...and he's a guy I'll never forget.
CFL: Craig Schaefer--personally ended Turner Gill's career...then went to prison for coke and man slaughter...I believe. Doesn't mean the dude couldn't play ball. He was a friggin' beast. No fear...