The Gaia Manuscripts (ガイア原稿, Gaia Genkou) is an important object that appears in the Unleashed Saga. These manuscripts are an ancient collection of documents, records and knowledge concerning a legendary disaster caused by the previous emergence of Dark Gaia, which occurred some tens of thousands of years before the events of the Unleashed Saga. They were initially stolen by Dr. Eggman prior to the game in his attempt to awaken Dark Gaia, but they were reclaimed by Sonic and his friends who later used them to undo the doctor's work.
Some tens of thousands of years prior to Sonic Unleashed, Dark Gaia followed its natural cycle and awoke from its slumber within the Earth's core, now having matured enough to attempt destroying the planet once more. As a result of its awakening, Dark Gaia broke the planet into pieces in an event that would be passed down into legend as a legendary cataclysm that threaten the existence of the world.
True to the cycle however, the crisis was averted by Light Gaia, who defeated Dark Gaia, returned it to the core and restored the planet to normal. At some point during or after the cataclysm, the events and the knowledge that were gained from the event, was recorded by an unknown civilization. These records would then become known as the Gaia Manuscripts.
In the present day, the Gaia Manuscripts came into the possession of Professor Pickle Rogers of Spagonia University, who became an expert on the subject. The Gaia Manuscripts (and Professor Pickle) were however stolen by Dr. Eggman, two weeks before the beginning of the Unleashed Saga, who sought to awaken Dark Gaia prematurely and use its essence to build Eggmanland. With the knowledge found within the Gaia Manuscripts' contents, Dr. Eggman devised a way for him to awaken the great beast, namely his Chaos Energy Cannon. The doctor then later stored the Gaia Manuscripts within a vault in his base in Mazuri, where he also kept Professor Pickle prisoner.
After Dr. Eggman succeeded in awakening Dark Gaia and breaking apart the Earth, Pofessor Pickle was freed by Sonic the Werehog, Tails and Light Gaia (nicknamed Chip) and the group reclaimed the Gaia Manuscripts as they contain information that was needed to restore the planet. With the info provided by the Gaia Manuscripts, Professor Pickle formulated a plan of action for Sonic and enlisted him to seek out the Temple of Gaias enlisted in the Gaia Manuscripts to restore the planet.
The Gaia Manuscripts remained in the care of Professor Pickle for the remainder of the adventure, who continued to research them for additional information. The information contained within them proved to be a great assist to Sonic, such as providing him with the location of the Gaia Temples and uncover the way for him and Chip to free people from the influence of Dark Gaia's minions.
The Gaia Manuscripts contained an encyclopedia of knowledge concerning everything connected to the disaster created by Dark Gaia's awakening, such as recordings of the disaster, info on the Gaia Temples and their location, the nature and weaknesses of Dark Gaia's minions, a detailed description of Dark Gaia and its being and scenarios of what would happen should Dark Gaia succeeded in its mission. These texts are written in an ancient language that so far only Professor Pickle has been able to decipher.
- "The abomination grows strong on the negative energies of the world, sleeping within its core for millennia in wait..." - Gaia Manuscripts, 4:11.
- "When the beast is complete, its dark arms shall encompass the planet, ushering in the end of times. The world, in death, will fall into a deep sleep in waiting for the time of rebirth to come." - Gaia Manuscripts, 4:28.
- "And the world shall be plunged into the dark of night, the dark of destruction." - Gaia Manuscripts.
- "Light shall put out darkness to rout." - Gaia Manuscripts.