Karnak, Bringer of Storms

Flying, hexproof, indestructible
Karnak, Bringer of Storms power is equal to the number of instant and sorcery cards in your hand.
{0}: Instant and sorcery spells you control have storm. until end of turn. Activate this ability only if you have cast another spell this turn.
Whenever you cast an instant or sorcery spell, exile the top five cards of your library.