Vaporous Djinn is a uncommon Creature — Djinn card from Mirage (MIR), collector number 101. Current market price: $0.13, TCGplayer market prices via Scryfall.
Flying At the beginning of your upkeep, this creature phases out unless you pay {U}{U}. (While it's phased out, it's treated as though it doesn't exist. It phases in before you untap during your next untap step.)