Rooftop Storm 
Enchantment
You may pay 
rather than pay the mana cost for Zombie creature spells you cast.
Legality
standardNOT LEGALpioneerNOT LEGALmodernLEGALlegacyLEGALvintageLEGALcommanderLEGAL
Enchantment
You may pay rather than pay the mana cost for Zombie creature spells you cast.