Is Vedalken Shackles legal in Standard, Modern, and Commander?

Vedalken Shackles is legal in: Modern, Legacy, Vintage, Commander.

What type of card is Vedalken Shackles?

Vedalken Shackles is an Artifact. Its oracle text reads: "You may choose not to untap this artifact during your untap step. {2}, {T}: Gain control of target creature with power less than or equal to the number of Islands you control for as long as this artifact remains tapped."