Is Rubinia Soulsinger legal in Standard, Modern, and Commander?

Rubinia Soulsinger is legal in: Legacy, Vintage, Commander.

Rubinia Soulsinger

Q: What type of card is Rubinia Soulsinger?

Rubinia Soulsinger is a Legendary Creature — Faerie. Its oracle text reads: "You may choose not to untap Rubinia Soulsinger during your untap step.{T}: Gain control of target creature for as long as you control Rubinia and Rubinia remains tapped."

Legendary Creature — Faerie

You may choose not to untap Rubinia Soulsinger during your untap step.<br>: Gain control of target creature for as long as you control Rubinia and Rubinia remains tapped.