Basically, if you or an enemy gets hit, you roll dice to determine where the hit lands, and how badly it hurts whoever it hits.
A primary roll is made on a d4. This determines if you got hit in the head, torso, arms or legs.
A second roll is made to localize the damage
Head - d4: skull, neck, face, back of head
Torso - d6: crotch, butt, stomach, back, left chest, right chest
Arms - d4: hands, funny bone, arms, shoulders
Legs - d4: feet, shins, knees, thighs
I may revise this to add more bodyparts or change them.
Anyway, after you've determined where it hits, you roll a d10 to see how much damage it does.
Lower = less lethal, higher = YOU GON' DIE
Say you've been hit in the left chest. The damage roll lands on an 8. This is probably going to involve broken ribs if the weapon is blunt, pierce lungs if it is sharp, etc. If it is a 1, then you may only be knocked down or just get a really nasty bruise.