1 / 1
You may choose not to untap this creature during your untap step.

: Gain control of target legendary creature for as long as you control this creature and this creature remains tapped.
Once the ability resolves, it doesn’t care whether the targeted permanent remains a legal target for the ability, only that it’s on the battlefield. The effect will continue to apply to it even if it gains shroud, stops being a creature, stops being legendary, or would no longer be a legal target for any other reason.