Is Petrahydrox legal in Standard, Modern, and Commander?

Petrahydrox is legal in: Modern, Legacy, Vintage, Commander, Pauper.

Petrahydrox

Q: What type of card is Petrahydrox?

Petrahydrox is a Creature — Weird. Its oracle text reads: "({U/R} can be paid with either {U} or {R}.) When this creature becomes the target of a spell or ability, return this creature to its owner's hand. *It departs through the streets' fissures with a sound like gravel pouring into a pond.* Power/Toughness: 3/3"