Black Iron Tarkus

Black Iron Tarkus can't be dealt damage by equipped creatures with artifacts containing the words "Dark Steel" and can't be the target of spells, abilities, or permanents containing the words "Dark Steel"
Undead Curse- If life was used to pay for Black Iron Tarkus's mana cost then, destroy target artifact, if target artifact would be indestructible, ignore that ability and destroy it instead.