Pests of Honor is a uncommon Creature — Mouse card from Wilds of Eldraine (WOE), collector number 310. Current market price: $0.27 (foil $0.25), TCGplayer market prices via Scryfall.
Celebration — At the beginning of combat on your turn, if two or more nonland permanents entered the battlefield under your control this turn, put a +1/+1 counter on this creature.