Scurrilous Sentry is a common Creature — Human Knight Rogue card from Modern Horizons 3 (MH3), collector number 108. Current market price: $0.11 (foil $0.27), TCGplayer market prices via Scryfall.
Menace Whenever this creature enters or attacks, it connives. (Draw a card, then discard a card. If you discarded a nonland card, put a +1/+1 counter on this creature.)