Is Invert the Skies legal in Standard, Modern, and Commander?

Invert the Skies is legal in: Modern, Legacy, Vintage, Commander.

What type of card is Invert the Skies?

Invert the Skies is an Instant. Its oracle text reads: "Creatures your opponents control lose flying until end of turn if {G} was spent to cast this spell, and creatures you control gain flying until end of turn if {U} was spent to cast this spell. (Do both if {G}{U} was spent.)"

Invert the Skies

Instant

Creatures your opponents control lose flying until end of turn if was spent to cast this spell, and creatures you control gain flying until end of turn if was spent to cast this spell. (Do both if was spent.)