Invert the Skies (EVE) from Eventide, available at 401 Games Canada.

• Rarity: Uncommon
• Finish: Normal
• Artist: Randy Gallegos
• Card Text:
  Creatures your opponents control lose flying until end of turn if G was spent to play Invert the Skies, and creatures you control gain flying until end of turn if U was spent to play it. (Do both if GU was spent.)