Smallville, Luthor, Season 10 Episode 10, Aired December 3rd, 2010 on the CW!
After fighting with AULionel and getting a little help from AUOliver, Clark uses the mirror box to come home to a Watchtower that has been nearly destroyed by Clark Luthor in his place. Lois confirms to Oliver and Tess, within moments, that Clark Kent is back.
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