Impending Doom 
Enchantment — Aura
Enchant creature Enchanted creature gets +3/+3 and attacks each combat if able. When enchanted creature dies, this Aura deals 3 damage to that creature's controller.
Legality
standardNOT LEGALpioneerLEGALmodernLEGALlegacyLEGALvintageLEGALcommanderLEGAL