The Lyoko Warriors (also referred to as "Team Lyoko", "the group", or "the gang") is the name given to the group of main characters in Code Lyoko; Ulrich Stern, Yumi Ishiyama, Aelita Schaeffer, Jeremie Belpois, Odd Della Robbia, and later William Dunbar. The Lyoko Warriors battle the evil, multi-agent computer program named X.A.N.A. so that he does not gain control of Earth. They also try to gain more knowledge about Aeita, Franz Hopper, and X.A.N.A.. The Lyoko Warriors are constantly at odds with Sissi's group.
The current incarnation consists of six junior high schoolchildren and a canine.
- Ulrich Stern - Ulrich is hot-headed, stubborn, and shy, although loyal and thoughtful. In the first season, Ulrich was the apparent leader in Lyoko, however his role as this was diminshed in the following seasons. Ulrich is a samurai on Lyoko, with the abilities to split into three ("triplicate") and run very quickly ("super sprint"). His weapon is a sword, although in the fourth season, he was given katanas (dual swords). Ulrich is Yumi's love interest and their relationship is, to say the least, "complicated".
- Yumi Ishiyama - Yumi is the mature one of the group, that is, the person who offers common sense and ideas when the others are too incompetent or scared. Yumi is the oldest and is somewhat the leader, however this role is not "officially" established. Yumi is a geisha on Lyoko, reflecting her Japanese heritage and has the ability to move things with her mind ("telekinesis"). She is also gifted in aerobatics as she can balance herself in sticky situations. She is Ulrich's love interest, however throughout the show, she states that she is not interested but this proves not to be the case.
- Odd Della Robbia - Odd is of jokester of the team, and he constantly makes jokes constantly, much to his team members' annoyance. Odd has blonde hair with a purple streak. Odd is messy, disorganized, and cheap although he is loyal and honest. Odd acts more of a member than a leader, although he has taken command on occasion, especially in Marabounta. Odd is a cat on Lyoko and defends himself with laser arrows and his shield. Odd originally had the ability to see the future, however this was ability was later removed.
- Jeremie Belpois - Jeremie is more often than not the team's main leader strategist, as well as their source of intelligence. Jeremie acts as "the operatior"; he manages everything for virtualizing and devirtualizing, anything that does with the Supercomuter. He is Aelita's love interest and their relationship has been featured on the series, although not as heavily and Ulrich's and Yumi's.
- Aelita Schaeffer - Aelita was originally thought to be just a program until she was materialized and her history was revealed. She has the ability to use the interfaces in Lyoko. Originally a defenseless elf on Lyoko, Aelita becomes a strong angel (with wings) in the fourth season. Her main weapon is energy fields which can destroy monsters on contact (excluding Megatanks) and she also possesses
- William Dunbar - The newest addition to the team, William is immature when it comes to fighting X.A.N.A., much to the annoyance of his team members. On his first battle on Lyoko, he was possessed by X.A.N.A. and destroyed the Core. For the most part in the fourth season, William was possessed and battled the group in addition to X.A.N.A's monsters, until being rescued in Down to Earth. William is the only other member of the group that is the same age as Yumi.
- Kiwi - The only non-human member of the group. Kiwi was brought to Kadic as Odd's pet, much to the dismay of Ulrich. Kiwi has displayed a high degree of intelligence, and has proven useful to the group on occasion. Kiwi was supposed to be the first one to go into Lyoko, but Odd became the test subject instead with his attempt to save the dog in X.A.N.A. Awakens. Kiwi also helped Odd reload his arrows once, although accidentally.
Temporary members and aidesEdit
- Jim Morales - member in Code: Earth and False Start. Having been fired by the principal for breaking Jeremie's ankle during a heated chase, he decided to prove himself by assisting in the battle against materializedRoachsters and was supportive and kind to Aelita, even checking her pulse and speaking very respectfully to her. His memory was erased by time reversion, though Jim has proven himself many times after this. Jeremie even said at the end of the episode Opening Act that he was tired of explaining the concept of Lyoko to Jim, as a time reversion was about to take place.
- Herb Pichon - brief member in The Robots. He helped take down a robot X.A.N.A. created. His memory erased by time reversion.
- Sissi Delmas - member in Ultimatum, when she operated the Supercomputer. Memory erased by time reversion. She was going to be virtualized in X.A.N.A. Awakens, but was later deemed a traitor by Ulrich when she breaks her promise not to tell anyone about Lyoko. Sissi joins the group in the series finale.
- Chris Morales - brief member in Opening Act by helping the grouphold off a polymorphic clone during a battle. Memory erased by a return in time.
- X.A.N.A. - a temporary truce between Team Lyoko and X.A.N.A. occured in Marabounta as Aelita was being targeted due to X.A.N.A's virus. X.A.N.A. needed her memory and thus helped destroy the Marabounta. This truce however only lasted for one episode and a similar event didn't reappear until Common Interest, where X.A.N.A. helped Jeremie save Aelita and X.A.N.A. in the process by replacing the supercomputer's powersource.
- Patrick Belpois - appeared in one episode and also Jeremie's cousin. He helped stall the X.A.N.A.- possessedSissi and Herb. His memory was erased since Jeremie asked Aelita to activate a time reversion to heal his injuries from the attack of a possessed Sissi.