Hakbal of the Surging Soul is a mythic Legendary Creature — Merfolk Scout card from The Lost Caverns of Ixalan Commander (LCC), collector number 29. Current market price: $2.20 (foil $3.51), TCGplayer market prices via Scryfall.
At the beginning of combat on your turn, each Merfolk creature you control explores. (Reveal the top card of your library. Put that card into your hand if it's a land. Otherwise, put a +1/+1 counter on the exploring creature, then put the card back or put it into your graveyard.) Whenever Hakbal attacks, you may put a land card from your hand onto the battlefield. If you don't, draw a card.