Enchantment — Aura, G (1)
Rare
Enchant artifact
Whenever you're dealt damage, put that many vitality counters on Living Artifact.
At the beginning of your upkeep, you may remove a vitality counter from Living Artifact. If you do, you gain 1 life.
Illus. Anson Maddocks

10/4/2004: You can cast it targeting your opponent's artifacts. The controller of the Aura (not the controller of the artifact) controls the Living Artifact ability.
10/4/2004: Does not trigger on loss of life, just on damage.
Legal in Vintage (Type 1)
Legal in Legacy (Type 1.5)
Legal in Commander