Gravelgill Scoundrel is a common Creature — Merfolk Rogue card from Lorwyn Eclipsed (ECL), collector number 53. Current market price: $0.18 (foil $0.24), TCGplayer market prices via Scryfall.
Vigilance Whenever this creature attacks, you may tap another untapped creature you control. If you do, this creature can't be blocked this turn.