Would harm have a beneficial effect (eg restore the barbarian to 1d4 hp) if he was already minus? Thought this would be an interesting moment, when the cleric discovers that his spell actually helped. Ok, I don't really think this would work, but the spell description doesn't mention anything about what happens if the character is already below 0 hp. So how much damage would this spell put on top of the already -hp of the frenzying barbarian? Or would it simply have no effect?