Is The Master, Transcendent legal in Standard, Modern, and Commander?

The Master, Transcendent is legal in: Legacy, Vintage, Commander.

The Master, Transcendent

Q: What type of card is The Master, Transcendent?

The Master, Transcendent is a Legendary Artifact Creature — Mutant. Its oracle text reads: "When The Master enters, target player gets two rad counters. {T}: Put target creature card in a graveyard that was milled this turn onto the battlefield under your control. It's a green Mutant with base power and toughness 3/3. (It loses its other colors and creature types.) Power/Toughness: 2/4"

Legendary Artifact Creature — Mutant

When The Master enters, target player gets two rad counters.

: Put target creature card in a graveyard that was milled this turn onto the battlefield under your control. It's a green Mutant with base power and toughness 3/3. (It loses its other colors and creature types.)