Is Dragon's Herald legal in Standard, Modern, and Commander?

Dragon's Herald is legal in: Modern, Legacy, Vintage, Commander.

Dragon's Herald

Q: What type of card is Dragon's Herald?

Dragon's Herald is a Creature — Goblin Shaman. Its oracle text reads: "{2}{R}, {T}, Sacrifice a black creature, a red creature, and a green creature: Search your library for a card named Hellkite Overlord, put it onto the battlefield, then shuffle."

Creature — Goblin Shaman

, , Sacrifice a black creature, a red creature, and a green creature: Search your library for a card named Hellkite Overlord, put it onto the battlefield, then shuffle.