Cosmos, Aether Twin

Prowess, hexproof
Whenever you cast a spell, if that spell is blue, red, and green, put an aether counter on Cosmos.
{r}, Remove an aether counter from Cosmos: The next spell you cast this turn deals damage equal
to its converted mana cost to each opponent.
{g}, Remove an aether counter from Cosmos: The next time a land enters the battlefield this turn, you may search your library for a land card and put it into your hand.