Strikes only, eh? How about a knife hand directed 2" past his Adam's apple. If there's some dumb rule that you aren't supposed to kill him, then stomp on his foot. Stomp the heel of your biker boot onto his sandal. Stomp with all your might, then follow up with an eye gouge. Unless there's a pussy rule that you can't blind him either. In that case, stomp his foot again. Then stomp further and further up his leg as the rules will allow.