Marauding Mako is a uncommon Creature — Shark Pirate card from Aetherdrift (DFT), collector number 419. Current market price: $2.09 (foil $3.42), TCGplayer market prices via Scryfall.
Whenever you discard one or more cards, put that many +1/+1 counters on this creature. Cycling {2} ({2}, Discard this card: Draw a card.)