Sharktocrab is a uncommon Creature — Shark Octopus Crab card from Ravnica Allegiance (RNA), collector number 206. Current market price: $0.31 (foil $0.58), TCGplayer market prices via Scryfall.
{2}{G}{U}: Adapt 1. (If this creature has no +1/+1 counters on it, put a +1/+1 counter on it.) Whenever one or more +1/+1 counters are put on this creature, tap target creature an opponent controls. That creature doesn't untap during its controller's next untap step.