Is Gregor, Shrewd Magistrate legal in Standard, Modern, and Commander?

Gregor, Shrewd Magistrate is legal in: Legacy, Vintage, Commander.

Gregor, Shrewd Magistrate

Q: What type of card is Gregor, Shrewd Magistrate?

Gregor, Shrewd Magistrate is a Legendary Creature — Human Advisor. Its oracle text reads: "Skulk (This creature can't be blocked by creatures with greater power.) Whenever Gregor, Shrewd Magistrate deals combat damage to a player, draw cards equal to its power. Power/Toughness: 1/3"