Benthokrasis, Deep Regent

As long as there are eight or more creature cards in your graveyard, Krakens, Leviathans, Octopuses, and Serpents you control get +3/+3 and have islandwalk.
{u}{b}{b}: Search your library for a Kraken, Leviathan, Octopus, or Serpent card, put it into your graveyard, then shuffle.