Poseidon, God of the Sea

Idestructible
As long as your devotion to blue and black is less
than seven, Poseidon isn't a creature.
Kraken, Leviathen, Octopus, and Serpent
creatures gain {u}{t}: Target sea creature gains hexproof until end of turn.
Anytime a sea creature would die, target
opponent puts the top X cards of his or her
library into his or her graveyard, where X is that creature's power.