Is Chronomancer legal in Standard, Modern, and Commander?

Chronomancer is legal in: Legacy, Vintage, Commander.

What type of card is Chronomancer?

Chronomancer is an Artifact Creature — Necron Wizard. Its oracle text reads: "Flying Atomic Transmutation — {1}, {T}, Sacrifice another artifact: Draw a card. Unearth {2}{B} ({2}{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.)"

Chronomancer

Artifact Creature — Necron Wizard

Flying

Atomic Transmutation — , , Sacrifice another artifact: Draw a card.

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.)