The Gaia Manuscripts were a series of texts that featured in Sonic Unleashed.
The Manuscripts were an ancient series of texts that told a legend of a disaster that befell the Earth roughly tens of thousands of years ago. According to the scroll, the planet had been split apart into many pieces in the distant past with the cause lying in the very heart of the world. The phenomena was the direct result of one creature which caused a number of phenomena around the Earth. This was the hyper energy organism that spawned at the very heart of the planet which was Dark Gaia.
The scroll also indicated a number of temples around the world which was the key to restoring power to the Chaos Emeralds which in turn would restore the Earth back to normal. These included the Temple of Gaia.
The scripts state: "And the world shall be plunged into the dark of night, the dark of destruction."