Is Tifa's Limit Break legal in Standard, Modern, and Commander?

Tifa's Limit Break is legal in: Standard, Modern, Pioneer, Legacy, Vintage, Commander, Historic.

What type of card is Tifa's Limit Break?

Tifa's Limit Break is an Instant. Its oracle text reads: "Tiered (Choose one additional cost.) • Somersault — {0} — Target creature gets +2/+2 until end of turn. • Meteor Strikes — {2} — Double target creature's power and toughness until end of turn. • Final Heaven — {6}{G} — Triple target creature's power and toughness until end of turn."