Digimon Chronicle Story: Hork + Hikumi are creditied for the translation of the official Chronicle site so full credit to the, for this.

History: (Pages 1 and 2 of Digimon Chronicle's Offical Site)

A Computer Virus which had Artificial Intelligence spread through the world one day. The Virus changed a Digital Monster's (Digimon) figure and character. Then it evolved just like a life form while on the network! The Digi-Core (Digital-Core), which manages all Digimon, is the program and data that makes a Digimon live. What you see (A monster, cyborg, etc.) is based on information from the Digi-Core A Digimon is born from a Digi-Tama (Digital Egg). It will then grow up. If a program or data is eaten (like food) or if it wins a battle, a figure will be changed and it will Evolve! It will die and return to a Digi-Tama, again.

There are different Levels of Evolution Digimon can reach. The Ultimate Level (Mega) is the highest level. When a Digimon reaches the Ultimate Level, it can become a powerful weapon. In the Network of the Real World, it probably would be... The world where Digimon live is the Digital World. The host computer, Yggdrasil of Mystery, has managed everything in the Digital World. According to a report, it is said that Digimon are a life form produced by Yggdrasil's experiments in the Digital World...

However, the Digimon's large amount of Data exceeded Yggdrasil's predictions and it threatened a Digital Hazard. THE DIGITAL WORLD IS ON THE VERGE OF COLLAPSE!! "Evolution" is when a Digimon generates enough data, then evolves to fill it. Furthermore, an influx of data into the Digital World through a network can trigger an irregular evolution. A plan called "Project Ark" removes all Digimon and uploads the required Royal Knights and Digimon used as candidates for research about the new World by Yggdrasil.

X Digimon: (Page 3 of Digimon Chronicle's Offical Site)

Surviving Digimon and Others were Discovered!! Only strong Digimon were able to survive by changing their Digi-Core. Those Digimon are surely unknown! The Digimon were re-born in a form that could take in the X-Program! It came to a point where the program that opposes the X program was installed into the Digi-Core. It is called X Antibody.

The X Antibodies soon influenced the Digi-Core and had the capability to pull out High-Level information from the Digi-Core. Therefore, the potential capabilities can be demostrated at such a high level that conventional Digimon are nothing compared it. Furthermore, the Digimon's form is also changed do to the influence.

However, if the X Antibodies in the Digi-Core continue to be infected with the X Program, they will be destroyed. Death was feared and the World's law was survival of the fittest. Everyone scammbled to get the power of the X Antibody to strengthen themselves. The surviving Digimonwent to a new world, the NEW Digital World where the X program could not reach them...

NEW Digital World: (Page 4 of Digimon Chronicle's Offical Site)

The Digital World's Highest Level of security, the Saintly horsemen called the Royal Knights.Even though they are Saintly horsemen, they do not fight completely for good, but rather for whatever "justice" they see as "right." They say there are 13 Royal Knights (We already know 2 from Frontier RhodoKnightmon + Dynasmon)

The NEW Digital World is divided into three layers. It consists of the Future Layer, Past Layer, and Present Layer. The Future Layer contains Artificial Evolution Digimon. The Past Layers has Ancient types, such as Dinosaur types. All kinds of Digimon are born in the Present Layer. Crossing the layers moves you between time in in this World's eras The NDW is a safe, virtual experiment space coming from a Host computer, but does not accumulate data to the Host Computer itself. The three layers are known as the "Chronicle Layer System" and are suited for each layer's Digimon's evolution.

X Antibodies have influenced the Digimon itself. There is a power which pulls out the potential capability of a Digimon to the maximum extent when it's life depends on it (hunger, muscular strength circumstances, etc.) and makes them Evolve (especially during an attack). A "XAI system" is a system which displays the situation of the X Antibodies.

The X-Antibody Indicator is commonly called XAI (Pronounced "SAI") System.

When Digimon with X Antibodies were discovered, the host computer, although originally pursuit and surveillance based, succeeded in miniaturizing them, and made loading them possible using the Pendulum X