Spectral Adversary is a mythic Creature — Spirit card from Innistrad: Double Feature (DBL), collector number 77. Current market price: $1.79 (foil $5.12), TCGplayer market prices via Scryfall.
Flash Flying When this creature enters, you may pay {1}{U} any number of times. When you pay this cost one or more times, put that many +1/+1 counters on this creature, then up to that many other target artifacts, creatures, and/or enchantments phase out.