Is Mole Worms legal in Standard, Modern, and Commander?

Mole Worms is legal in: Legacy, Vintage, Commander.

What type of card is Mole Worms?

Mole Worms is a Creature — Worm. Its oracle text reads: "You may choose not to untap Mole Worms during your untap step.{T}: Tap target land. It doesn't untap during its controller's untap step for as long as Mole Worms remains tapped."

Mole Worms

Creature — Worm

You may choose not to untap Mole Worms during your untap step.<br>: Tap target land. It doesn't untap during its controller's untap step for as long as Mole Worms remains tapped.