Swimmer in Nightmares [Theros Beyond Death]

Set: Theros Beyond Death Type: Creature — Nightmare Merfolk Rarity: Uncommon Cost: {2}{U} Swimmer in Nightmares gets +3/+0 as long as there are ten or more cards in a single graveyard. Swimmer in Nightmares can't be blocked as long as you control an Ashiok planeswalker. Ashiok's minions plumb the depths of the ocean and the psyche.