Is Agent of Erebos legal in Standard, Modern, and Commander?

Agent of Erebos is legal in: Modern, Pioneer, Legacy, Vintage, Commander.

Agent of Erebos

Q: What type of card is Agent of Erebos?

Agent of Erebos is an Enchantment Creature — Zombie. Its oracle text reads: "Constellation — Whenever this creature or another enchantment you control enters, exile target player's graveyard. *Erebos's minions hunt the Returned and warn those who consider the same folly.* Power/Toughness: 2/2"