Is Xantcha, Sleeper Agent legal in Standard, Modern, and Commander?

Xantcha, Sleeper Agent is legal in: Legacy, Vintage, Commander.

Xantcha, Sleeper Agent

Q: What type of card is Xantcha, Sleeper Agent?

Xantcha, Sleeper Agent is a Legendary Creature — Phyrexian Minion. Its oracle text reads: "Xantcha enters under the control of an opponent of your choice. Xantcha attacks each combat if able and can't attack its owner or planeswalkers its owner controls. {3}: Xantcha's controller loses 2 life and you draw a card. Any player may activate this ability. Power/Toughness: 5/5"