Arterial Alchemy is a rare Enchantment card from Magic Online Promos (PRM), collector number 95367.
When this enchantment enters, create a Blood token for each opponent you have. (It's an artifact with "{1}, {T}, Discard a card, Sacrifice this token: Draw a card.") Blood tokens you control are Equipment in addition to their other types and have "Equipped creature gets +2/+0" and equip {2}.