Is Triarch Praetorian legal in Standard, Modern, and Commander?

Triarch Praetorian is legal in: Legacy, Vintage, Commander.

What type of card is Triarch Praetorian?

Triarch Praetorian is an Artifact Creature — Necron. Its oracle text reads: "Flying Dynastic Codes — When this creature enters from a graveyard, you draw two cards and you lose 2 life. Unearth {4}{B} ({4}{B}: Return this card from your graveyard to the battlefield. It gains haste. Exile it at the beginning of the next end step or if it would leave the battlefield. Unearth only as a sorcery.) Power/Toughness: 2/1"

Triarch Praetorian

Artifact Creature — Necron

Flying

Dynastic Codes — When this creature enters from a graveyard, you draw two cards and you lose 2 life.

Unearth (: Return this card from your graveyard to the battlefield. It gains haste. Exile it at the beginning of the next end step or if it would leave the battlefield. Unearth only as a sorcery.)