Xia rolls a 6!
Pay no attention to that
its just my way of keeping track of battle fatigue for my own alts.
Basically I give them HP. Baring an event that would spell instant death for them, when they are in a fight, get hurt, get tired etc etc I roll a die and subtract the result.
When it gets down to 0 they get injurred or knocked out or even killed, depending on the situation.