Bound by Moonsilver is a uncommon Enchantment — Aura card from Shadows over Innistrad (SOI), collector number 7. Current market price: $0.10 (foil $0.24), TCGplayer market prices via Scryfall.
Enchant creature Enchanted creature can't attack, block, or transform. Sacrifice another permanent: Attach this Aura to target creature. Activate only as a sorcery and only once each turn.