Time of awakening

The  is a major global event that occurs on Earth once for every couple of millions of years. During this event, the Earth is broken apart by the ancient creature known as Dark Gaia, following the beast return to full maturity, in an attempt to destroy the world. After this cataclysmic break-up has occured, the world is then put back together by Light Gaia, who awakens at the same time and returns Dark Gaia to dormancy.

Origin
The Time of Awakening has occured on Earth ever since the the beginning of time. When Dark Gaia and Light Gaia appeared on Earth at the time where the planet began, Dark Gaia turned out to desire the planet's destruction. To protect the planet from Dark Gaia's wrath, however, Light Gaia assumed the duty of protecting this world from his dark counterpart. Eventually, Dark Gaia was stopped, stripped of its power, and ended up in Earth's core, where it went to sleep to regain its strength. Light Gaia himself presumably went to sleep in the Earth's core as well, to await the day where Dark Gaia would rise again. The time where Dark Gaia and Light Gaia would then awaken, rising up to their full potential, would then be known as the Time of Awakening.

Following the two entities going into dormancy, the endless conflict between Dark Gaia and Light Gaia began, with the Time of Awakening marking the climax of their conflict. In this cycle, Dark Gaia would gather negative energy from the world in its sleep over millions of years. Once it had gather enough power it would emerge from the core as Perfect Dark Gaia, splitting the world apart. Light Gaia would then awaken as well, thus marking the beginning of the Time of Awakening. Light Gaia would then return Dark Gaia to sleep, weaken, and restore the Earth to its former state, before going back to sleep as well, ending the Time of Awakening. This cycle and the Time of Awakening has since repeated itself countless times for eons to come and continues to this day.

Premature Time of Awakening
In Sonic Unleashed, Dr. Eggman planned to harness Dark Gaia's energies in an attempt to establish Eggmanland. To do so, the doctor sought to awaken Dark Gaia by initiating the Time of Awakening himself with his Chaos Energy Cannon. By tricking Super Sonic into his Chaos Energy Cannon, Eggman managed to create a negative Chaos Energy blast that forced Dark Gaia to awaken and shatter the planet. This unnatural awakening, however, was not a considered a "proper Time of Awakening" by Light Gaia, as Dark Gaia had not reached full maturity, as it had only slept for a few tens of thousands of years and therefore broke apart, and Light Gaia lost his memory in the process.

At the time where Sonic the Hedgehog and Light Gaia (called Chip by Sonic) confronted the fully reasembled Dark Gaia in the Earth's core, Light Gaia called the Gaia Temples to to form the Gaia Colossus, and pronounced that the Time of Awakening now had truly arrived. With the help of Super Sonic, Light Gaia defeated Dark Gaia, bringing the Time of Awakening to an end once more. Dark Gaia and Light Gaia then went to sleep in the Earth's core until the next Time of Awakening.