Echoing the sentiment that, while I absolutely love Benison, it should only be using one Lily as opposed to... all of them - especially when the amount you have does not make it stronger or weaker. So having it consume all current Lilies is just a bit silly to me, and it isn't as though reducing the cost to 1 would make it OP. It still has a cooldown, so it's not as if you could be spamming Benison on the tank willy-nilly.