Sphinx-Bone Wand is a rare Artifact card from Duel Decks: Izzet vs. Golgari (DDJ), collector number 29. Current market price: $0.53, TCGplayer market prices via Scryfall.
Whenever you cast an instant or sorcery spell, you may put a charge counter on this artifact. If you do, this artifact deals damage equal to the number of charge counters on it to any target.