The Jolly Balloon Man is a rare Legendary Creature — Human Clown card from Duskmourn: House of Horror Promos (PDSK), collector number 219p. Current market price: $0.52 (foil $0.77), TCGplayer market prices via Scryfall.
Haste {1}, {T}: Create a token that's a copy of another target creature you control, except it's a 1/1 red Balloon creature in addition to its other colors and types and it has flying and haste. Sacrifice it at the beginning of the next end step. Activate only as a sorcery.