Living Artifact is a rare Enchantment — Aura card from Collectors' Edition (CED), collector number 209. Current market price: $1.99, TCGplayer market prices via Scryfall.
Enchant artifact Whenever you're dealt damage, put that many vitality counters on this Aura. At the beginning of your upkeep, you may remove a vitality counter from this Aura. If you do, you gain 1 life.