Remnant Project

The Remnant Project was the program being run by Xashowd and Hikaru. It's objective was to revive fallen members of Organization XIII, and to use them for certain desires to help bring peace to the worlds in Kingdom Hearts Legacy II.

The reviving process was based on the piecing together of remnant memories, hence the name "Remnant Project".

History
The project was originally planned and overseen by Xashowd, kept secret to the rest of the universe in Castle Oblivion.

Once, a former nobody had entered the castle, alerting Xashowd. Fearing that his intentions would be revealed to the rest of the universe, Xashowd placed a "spell" of sorts on Noah, and warped him to another world.

Later on, Hikaru entered, tracking down his brother in an attempt to reunite for their own plans. Xashowd once again tried to "dispose" of the intruder, but failed, and was rendered helpless by Hikaru.

Instead of destroying the nobody, Hikaru engaged Xashowd in a conversation and explained his intentions, and the two formulated a plan: In exchange for help with the Remnant Project, Xashowd would take Hikaru to Noah.

With help from Hikaru, Xashowd managed to revive Xigbar, going by the name of his original self, Braig.