S01E09 — How to Fool XANA

Jeremy and Aelita program false source codes that will destroy any specter that tries to take them from a Lyoko Warrior, and tests it using Ulrich as a guinea pig. Ulrich is told to wait at school until he spots a specter and deliberately touch it to transfer the fake source codes to it to test if they work. A specter with hypnotic abilities appears the same day. If the specter manages to catch someone's gaze, it can send them into a trance-like state which the specter can use to approach a Lyoko Warrior and take their actual source codes without them fighting back. Ulrich manages to test the false source codes and destroys the specter, but it knocks him unconscious for a while. Jeremy decides not to try it again as it is too risky.