Marrow-Gnawer is a rare Legendary Creature — Rat Rogue card from Secret Lair Drop (SLD), collector number 34. Current market price: — (foil $37.54), TCGplayer market prices via Scryfall.
All Rats have fear. {T}, Sacrifice a Rat: Create X 1/1 black Rat creature tokens, where X is the number of Rats you control.