|This article contains SPOILERS for the main story of CrossCode. Proceed at your own risk!|
|This article contains SPOILERS for the A New Home DLC of CrossCode. Proceed at your own risk!|
During the main game, the Evotar Server stores the data of all Evotars, with the exception of Lea, and runs their Avatars within CrossWorlds. It was kept within a dungeon instance so that Sidwell could remotely destroy it in order to prevent it from falling into the wrong hands, and protected by an access key that only allowed authorized avatars to approach it.
Before the events of CrossCode, Lea experienced a severe malfunction, which was implied to be caused by Shizuka confronting her about being an AI, and intentionally faked to seem worse by Satoshi. In an attempt to fix this malfunction, Sidwell brought Lea's avatar to the server so that they could be debugged side-by-side, providing Lea with an access key to the server. Satoshi pretended to be unable to fix the issue, and to delete Lea, but actually moved her off the Evotar Server onto one of CrossWorlds' main servers for Sergey to later find.
The goal of the Vermillion Raid at the end of the base game was to secure the Evotar Server, saving the Evotars stored on it. To prevent Sidwell from destroying the server, Sergey and Satoshi attempted to exploit an obscure bug in the Evotar Server's outdated software. Although they were able to successfully crash the server, Sidwell revealed that the means of destroying the server was actually by removing the dungeon environment around it, causing it to fall, which could be done even if the server itself was unresponsive. However, before he is able to do this, Gautham locks him out of Vermillion Tower's Environment Server and challenges Lea to complete his "Ultimate Experience" in exchange for access to the Evotar Server. After Gautham is defeated, he allows Lea to access the server and retrieve the Evotars.
The A New Home DLC reveals that there was a second Evotar Server which was used for Sidwell's Evotars, including the original C'tron. As very few people were aware of this server, it was not recovered, and the Evotars on it were most likely lost.