Is Keeper of the Dead legal in Standard, Modern, and Commander?

Keeper of the Dead is legal in: Legacy, Vintage, Commander.

Keeper of the Dead

Q: What type of card is Keeper of the Dead?

Keeper of the Dead is a Creature — Human Wizard. Its oracle text reads: "{B}, {T}: Choose target opponent who has at least two fewer creature cards in their graveyard than you do as you activate this ability. Destroy target nonblack creature that player controls. Power/Toughness: 1/2"

Creature — Human Wizard

, : Choose target opponent who has at least two fewer creature cards in their graveyard than you do as you activate this ability. Destroy target nonblack creature that player controls.