|William vs William|
|Air date||February 25, 2013|
|Written by||Josep Maria Roca Peña|
X.A.N.A. Is Stronger
Kiwi on Lyoko
It's 8 in the morning. Jeremy finds a Replika in the Digital Sea, and he's working on creating another Skidbladnir. He's also working to improve Sissi's clone, and especially to recover Sissi. Then appear Aelita, Odd and Ulrich saying it's time for breakfast. In the cafeteria, come Yumi and William, and all Lyoko-Warriors sit at breakfast watching Sissi's clone. Meanwhile, X.A.N.A. activates a tower and invokes the polymorphic clone of X.A.N.A.-William , and teleports it to Kadic as spectre. But the super-scanner is damaged and Jeremy isn't notified. When they finished breakfast, they go to their rooms.
Milly and Tamiya find X.A.N.A.-William with Lyoko uniform, and do a comment on the strange dress. He only answers asking where is Aelita. Later they find Aelita, and tell her that William was looking for her, and he has a stange dress. Aelita finds the real William, and he doesn't know nothing of the encounter with Milly and Tamiya. Aelita has suspicions. Again ask Milly and Tamiya, and they describe him as William was dressed and having a strange voice. Aelita quickly notifies Jeremy and the other, and go to the factory. There they find that X.A.N.A. has activated a tower and teleported X.A.N.A.-William.
Aelita, Odd, Ulrich, Yumi and William go to the ice sector of Lyoko to deactivate the tower . X.A.N.A.-William goes to the factory to attack the group. Then appear flying Tarantulas, Mantas and X.A.N.A.-Sissi. Odd handles tarantulas, Ulrich of Mantas, William of X.A.N.A.-Sissi and Aelita of the tower. Throughout this struggle, Odd is devirtualized and X.A.N.A.-William is waiting for him in real world. Aelita manages to confuse X.A.N.A.'s monsters and deactivates the tower, bringing X.A.N.A.-William back to Lyoko. Then X.A.N.A.-William fights against the real William and X.A.N.A.-Sissi against Yumi, and Yumi is devirtualized. But they have to go to Sector 5 to fix the super-scanner. They leave the tower avoiding X.A.N.A.-Sissi.
Ulrich, Aelita and William caught the Transport Orb and go to Sector 5 where the Scyphozoa tries to take control of William again. But Ulrich and Aelita make it run. X.A.N.A.-William appears, and begins a fight against the real William and X.A.N.A.-William, and finally the real William devirtualizes X.A.N.A.-William and scanner leaves a small chip that collects Aelita for examine.
They arrive at the terminal, where the Scyphozoa and X.A.N.A.-Sissi appears again, but Aelita fix the program and Jeremy devirtualizes the three. X.A.N.A.-Sissi screams for defeat. At the Factory all say it's better than not going William to Lyoko X.A.N.A. because X.A.N.A. wants to possess him by the Scyphozoa, but he says no need: parents of William will move and he leaves Kadic. At the end of the episode all Lyoko-Warriors say goodbye to William, and he goes with his parents. Jeremy, after the car is going, says to the group: "We have a chip of X.A.N.A. to examine" referring to the chip that was materialized when William devirtualized his clone.