The book was never published in English. The title used here is a translation.
- In Italian, the title was "L'esercito del nulla"
- In Spanish, the title was "El ejército de la nada"
- In Catalan, the title was "Ľexèrcit del no-res"
- In Galician, the title was "O exército da nada"
- In Basque, the title was "Ezerezaren Gudarostea"
- In Portuguese, the title was "O exército da nada"
- In Dutch, the title was "Het Leger Van De Afrekening"
With the Green Phoenix taking over the factory, Jeremie and his friends had to act fast to prevent a catastrophe. The story stars with Eva Skinner on Lyoko (having been virtualized there in the previous book) amazed by her virtual form of a Subdigital fan. She is not alone, as she is with Ulrich and Jeremie . Having broken the barrier between Lyoko and the First City, he saves his friends Ulrich and Eva Skinner from being virtualised there forever, but unfortunately the stronger X.A.N.A. has escaped and taken control Lyoko again.
Back in reality, Kadic has taken a huge blow from X.A.N.A.'s robots which were materialized into the real world in the previous book. In the wake of the destruction is Odd Della Robia and Yumi Ishiyama who are exhausted after the previous day's fighting. Despite having escaped the First City X.A.N.A. still cannot gain 100% power as the half was in the mirror ,another virtual sandbox which recounts the chapter preceding to his virtualization on Lyoko. This other form is stuck with Aelita who had suffered amnesia (probably because she and X.A.N.A. were linked together) and the mirror was an eye opener for her to learn about her long-lost father's past and involvement in the supercomputer, the virtual world of Lyoko, and the rouge multi-agent system/artificial intelligence X.A.N.A.
She sees her ten-year-old self sitting with twelve-year-old Richard .She also learns the reason of the palm computer's weird code .Being Aelita's best friend during that time, Franz Hopper entrusted him with a special email adress which was meant to help Aelita if she was in any trouble.That was during a time when emails were still at a young age hence it probably prompted him to remember it for life and still have it until then.
- Chapter 1:
- Chapter 2:
- Chapter 3:
- Chapter 4:
- Chapter 5:
- Chapter 6:
- Chapter 7:
- Chapter 8:
- Chapter 9:
- Chapter 10:
- Chapter 11:
- Chapter 12:
- Chapter 13:
- Chapter 14:
- Chapter 15:
- Chapter 16: