Invert the Skies
d6d0a6f9-478f-43c7-8591-3b601c12ed01
$0.50 CND
Creatures your opponents control lose flying until end of turn if {G} was spent to cast Invert the Skies, and creatures you control gain flying until end of turn if {U} was spent to cast it. (Do both if {G}{U} was spent.)