Warzone Duplicator is a rare Artifact Creature — Construct card from Alchemy: The Brothers' War (YBRO), collector number 30.
Prototype {3}{U} — 3/3 When this creature enters, return target creature an opponent controls with power less than this creature's power to its owner's hand. If that creature wasn't a token, conjure a duplicate of it into your hand. It perpetually gains prismatic.