Curse of Vitality 
Enchantment — Aura Curse
Enchant player Whenever enchanted player is attacked, you gain 2 life. Each opponent attacking that player does the same.
Legality
standardNOT LEGALpioneerNOT LEGALmodernNOT LEGALlegacyLEGALvintageLEGALcommanderLEGAL