Is Firebending Lesson legal in Standard, Modern, and Commander?

Firebending Lesson is legal in: Standard, Modern, Pioneer, Legacy, Vintage, Commander, Pauper, Historic.

What type of card is Firebending Lesson?

Firebending Lesson is an Instant — Lesson. Its oracle text reads: "Kicker {4} (You may pay an additional {4} as you cast this spell.) Firebending Lesson deals 2 damage to target creature. If this spell was kicked, it deals 5 damage to that creature instead."