Is Venomspout Brackus legal in Standard, Modern, and Commander?

Venomspout Brackus is legal in: Legacy, Vintage, Commander.

Venomspout Brackus

Q: What type of card is Venomspout Brackus?

Venomspout Brackus is a Creature — Beast. Its oracle text reads: "{1}{G}, {T}: This creature deals 5 damage to target attacking or blocking creature with flying. Morph {3}{G}{G} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)"