Loose Lips is a common Enchantment — Aura card from Unhinged (UNH), collector number 36. Current market price: $0.19 (foil $0.50), TCGplayer market prices via Scryfall.
Enchant creature As this Aura enters, choose a sentence with eight or fewer words. Enchanted creature has flying. Whenever enchanted creature deals damage to an opponent, that player may say the chosen sentence. If they don't, you draw two cards.