The Kolossus (known as Kolosse in French) is the largest and most powerful monster in Code Lyoko. It has only appeared in the Ice Sector and its Replika.

Appearance and Abilities

The Kolossus is X.A.N.A.'s strongest monster ever created, and also the biggest. It has the appearance of a giant, lava elemental being. It is impervious to any attack on its body, and its strength is so great, it can cause instant devirtualization and even destroy the Skid in a single hit. For X.A.N.A., however, the Kolossus' strength comes at the cost of requiring lots of energy to even generate it. In both Cold Sweat and Down to Earth, X.A.N.A. is seen drawing energy out of all the Replikas it had created to put the Kolossus onto the battlefield. When Jeremie launched a prototype X.A.N.A. Destruction Program, X.A.N.A. had to draw even more energy to allow the Kolossus to have the strength to free itself from the ice paralyzing it.

The Kolossus has four Eyes of X.A.N.A.. However, it is the large Eye of X.A.N.A. on its face and the one on its sword that must be hit to destroy it. Hitting any of the large Eyes individually does nothing to the Kolossus, as shown when Yumi threw a fan at the Eye of X.A.N.A. on its face. The fan was seemingly destroyed and the Kolossus seemed unhindered by the attack. However, when Ulrich pierced the Eye and kept his weapon there, the Kolossus was paralized until X.A.N.A. drew energy from all the Replikas to power up the Kolossus. Hitting any of the small Eyes on the sword makes the Kolossus halt for a short period of time.

If the Kolossus touches a tower, the part of the tower that the Kolossus is touching glows red - possibly because of the seemingly intense heat on its hands or because it's temporarily transferring data into the tower and bringing it under X.A.N.A.'s control, or both. The Kolossus destroys the Skid in Down to Earth by knocking it off the tower it was connected to, making it crash into the Digital Sea. In Fight to the Finish, the Kolossus was defeated by Ulrich, who was devirtualized soon after by the monster's body, which fell on top of him.


  • The monster's name was given by Odd in Cold Sweat. He spells it with "K" so it sounds like K.O., although Ulrich is not sure who will get K.O.-ed.
  • Ulrich is the only one so far to eliminate the Kolossus, by stabbing it in both of its Eyes of X.A.N.A. (one on its head, and one on its sword arm).
  • Odd once called the Kolossus "King Kong" in Down to Earth.
    • Odd also called the Kolossus "the Heap" in the same episode.
  • The creation of the Kolossus is a giant catalyst in the final episodes of the fourth season.
    • Revealing the number of Replikas made Jeremie think twice about the idea of destroying Replikas one by one.
    • Destruction of the Skid further convinced Jeremie to build the X.A.N.A. Destruction Program.
  • The fights against it are all of grave importance:
    • Freeing of William.
    • Destruction of the Skid and X.A.N.A.
  • The Kolossus has only appeared in Ice-related areas (the Ice Sector and its Replika).
  • The Kolossus appears as the final boss in the game, Fall of X.A.N.A..


Season 4

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