Monoist Circuit-Feeder is a uncommon Artifact Creature — Nautilus card from Edge of Eternities (EOE), collector number 110. Current market price: $0.14 (foil $0.29), TCGplayer market prices via Scryfall.
Flying When this creature enters, until end of turn, target creature you control gets +X/+0 and target creature an opponent controls gets -0/-X, where X is the number of artifacts you control.