Crashing Wave: Avatar: The Last Airbender

As an additional cost to cast this spell, waterbend {X}. (While paying a waterbend cost, you can tap your artifacts and creatures to help. Each one pays for {1}.) Tap up to X target creatures, then distribute three stun counters among tapped creatures your opponents control. (If a permanent with a stun counter would become untapped, remove one from it instead.)