Marchesa's Decree 
Enchantment
When this enchantment enters, you become the monarch. Whenever a creature attacks you or a planeswalker you control, that creature's controller loses 1 life.
Legality
standardNOT LEGALpioneerNOT LEGALmodernNOT LEGALlegacyLEGALvintageLEGALcommanderLEGAL