Opalash, Unseen Dweller

Cannot be Countered
Other Fish, Serpents, Krakens, and Leviathans you control get +2/+2 and gain hexproof.
{3}, Return a land you control to your hand: Choose an opponent. They discard up to three cards from their hand and exile a creature from their graveyard. That player cannot cast non-creature spells until their next turn.