Is Void Stalker legal in Standard, Modern, and Commander?

Void Stalker is legal in: Modern, Legacy, Vintage, Commander.

Void Stalker

Q: What type of card is Void Stalker?

Void Stalker is a Creature — Elemental. Its oracle text reads: "{2}{U}, {T}: Put this creature and target creature on top of their owners' libraries, then those players shuffle their libraries. *Now you see it, now you're gone.* Power/Toughness: 2/1"