You may have Wall of Stolen Identity enter the battlefield as a copy of any creature on the battlefield, except it's a Wall in addition to its other types and has defender (This creature can't attack.). When you do, tap the copied creature and it doesn't untap during its controller's untap step for as long as you control Wall of Stolen Identity.
The information presented on this site about Magic: The Gathering, both literal and graphical, is copyrighted by Wizards of the Coast.
This website is not produced, endorsed, supported, or affiliated with Wizards of the Coast.