Hangman is a rare Creature — Human Villain card from Unstable (UST), collector number 56. Current market price: $0.32 (foil $1.11), TCGplayer market prices via Scryfall.
As this creature enters, secretly note a word with six to eight letters. {1}: Target player who doesn't control this creature guesses the noted word or an unguessed letter in that word. If they guess wrong, put a +1/+1 counter on this creature. Any player may activate this ability. When a player guesses the noted word or all of its letters, sacrifice this creature.