Liar's Pendulum is a rare Artifact card from Mirrodin (MRD), collector number 196. Current market price: $0.89 (foil $15.09), TCGplayer market prices via Scryfall.
{2}, {T}: Choose a card name. Target opponent guesses whether a card with that name is in your hand. You may reveal your hand. If you do and your opponent guessed wrong, draw a card.