"Alysation: Invasion" is the fifteenth volume of the popular Japanese legendary series of legendary novels "Sword Art Online" by Reki Kawahara, which tells about the incredible adventures of the heroes in the virtual world. In this volume, the main characters, Kirito and his partner Yujio, find themselves in a new part of virtual reality, where a series of difficult tasks and dangers await them. The world the heroes enter is full of mysteries and threats, but they are ready to accept the challenge and do everything possible to defeat the enemies. Will they be able to pass all the challenges that will come their way? How will they feel and interact in this new reality? Readers will feel tension, emotion and excitement from every page of this fascinating story, which will not leave indifferent anyone who loves fantastic adventures in the virtual world.