A mudknuckle is when you take a shit,
smear your knuckles in it an then punch someone in the face.
Mudknuckles can be also delivered using other people's shit, dog shit, cat shit and/or
tiger shit. Basically you can use any poop available.
VARIATIONS:
A Hairy Mudknuckle is when you
dip your shit covered knuckles in pubic shavings before punching someone in the face.
A Mudknuckle Favor is when you smear your knuckles in shit and then pee on your knuckles to
rinse some of the poop of before punching someone in the face.