Reito Sentinel is a uncommon Artifact Creature — Construct card from Kamigawa: Neon Dynasty (NEO), collector number 256. Current market price: $0.28 (foil $0.39), TCGplayer market prices via Scryfall.
Defender When this creature enters, target player mills three cards. (They put the top three cards of their library into their graveyard.) {3}: Put target card from a graveyard on the bottom of its owner's library.