The Dark Monsters are the more powerful versions of the regular X.A.N.A. monsters, with a darker color palate. The only dark monster seen in the show is William's Black Manta. Dark Monsters have the same weaponry as their normal counterparts. However, their weapons do more damage and they have more life points. They were primarily seen in Code Lyoko: Quest for Infinity.
| Lyoko: Kankrelats | Hornet | Blok | Krab | Megatank | Creeper | Manta | Black Manta | Guardian | Tarantula | Scyphozoa | Kolossus
Earth:Spectre | Polymorphic Clone
Digital Sea: Kongre | Shark | Kalamar
Video game only: Mite | Exploding Roachsters | Scorpion | Insekt | Dark Monster | Volcanoid | Ubertank | Omegatank | Mountain Bug | Insekt Lord | Ice Spider | Desert Driller | Magma Worm