Mithril Coat is a mythic Legendary Artifact — Equipment card from The Hobbit Commander (HOC), collector number 43. Current market price: $26.37 (foil $33.21), TCGplayer market prices via Scryfall.
Flash Indestructible When Mithril Coat enters, attach it to target legendary creature you control. Equipped creature has indestructible. Equip {3}