Is Patron of the Valiant legal in Standard, Modern, and Commander?

Patron of the Valiant is legal in: Modern, Pioneer, Legacy, Vintage, Commander, Historic.

Patron of the Valiant

Q: What type of card is Patron of the Valiant?

Patron of the Valiant is a Creature — Angel. Its oracle text reads: "Flying When this creature enters, put a +1/+1 counter on each creature you control with a +1/+1 counter on it. *"Bant's most gallant knights wear my sigil, and for that I am humbled."* Power/Toughness: 4/4"