Spectral Adversary is a mythic Creature — Spirit card from Innistrad: Midnight Hunt Promos (PMID), collector number 77p. Current market price: $0.45 (foil $1.23), 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.