The Blackstaff of Waterdeep is a rare Legendary Artifact card from Adventures in the Forgotten Realms (AFR), collector number 48. Current market price: $0.33 (foil $0.24), TCGplayer market prices via Scryfall.
You may choose not to untap The Blackstaff of Waterdeep during your untap step. Animate Walking Statue — {1}{U}, {T}: Another target nontoken artifact you control becomes a 4/4 artifact creature for as long as The Blackstaff of Waterdeep remains tapped. Activate only as a sorcery.