Light Gaia, also known as Chip, is a character in Sonic Unleashed.
Chip was supposed to be named "Whip", in a reference to "whipped cream", which is the reason that whipped cream became an early design motif (for example, some early concepts had his hair like a dollop of whipped cream). However, because the word whip has different connotations in English (including the act of punishment, whipping, or suffering injury, as in the termwhiplash), Sega of America was not pleased with the name, so they changed the name to Chip.
Light Gaia is Chip's real name. Born in the beginning of time, Light Gaia is the opposite of Dark Gaia, and is the representation of light, day and rebirth. His purpose is to put the world back together when Dark Gaia destroys it. Dark Gaia dwells within the Earth's core for eons, feeding on the negative feelings and energies of the Earth's denizens, and emerging when it has grown strong enough. It is then Light Gaia's job to defeat Dark Gaia and return it to the Earth. Though he protected the planet over eons, Light Gaia never came to learn about the world itself.
He awoke alongside Dark Gaia when Dr. Eggman broke the world apart with his Chaos Energy Cannon. Due to this premature awakening, however, he lost his memories, forgetting who he was and his ancient duty. Shortly after, he is found by Sonic the Werehog, who had just landed on Earth after he had been ejected from Eggman's space ship. At first he was scared of Sonic in his Werehog form, but then he realizes that he means no harm. As they introduce themselves, Chip realizes that he had lost his memories and panics. Sonic assumes that he had fallen on him and had caused his amnesia, and as Chip calms down, Sonic promises him to help him regain his memories, which Chip is overjoyed about. Shortly after, as the day breaks, Chip witnesses Sonic's first transformation back to his old self, apparently amazed by it.
As the two of them arrive in Apotos, Chip's attention is caught by the local Ice Cream Vendor and his "Chocolate Chip Sundae Supreme", which he takes a instant liking to.
From then on, Chip follows Sonic on his adventure across the globe to put the planet back together. Along the way, they learn that Chip is able to activate the Gaia Temples which is needed to recharge the Chaos Emeralds and thus bring the world back together. This proves to be a valuable assist in Sonic's quest.
It is not until Sonic restores the sixth Chaos Emerald that he regains his memories, by touching a stone picture inside the sixth Gaia Temple. He explains to Sonic his and Dark Gaia's history, the cause of his memory loss and the reason why Sonic remains the same person, even in his Werehog form. He proceeds to thank Sonic for showing him the world he had protected for so long, but didn't know anything about and says he would never ever forget him. He then tries to continue on his own, since restoring the planet and defeating Dark Gaia is his job and that Sonic doesn't have to get involved, but Sonic convinces him to letting him help him anyway.
As they are in the process of restoring the final continent, Chip believes that it is all over and he thanks Sonic for all his help, but suddenly they are attacked by Eggman and his Egg Dragoon. Sonic manages to save Chip from the Egg Dragoon's initial attack and manages to defeat it after a hard battle that leads to the core of the planet, but then, the reassembled Dark Gaia emerges from the core and knocks Eggman away. It proceeds to fight Chip and Sonic, sucking out its power from Sonic that caused his Werehog transformation and regains all its lost power. It then tries to attack them again, but Chip saves them by creating a shield that protects them from Dark Gaia's assault.
In order to defeat Dark Gaia, Chip creates the Gaia Colossus out of the seven Temples of Gaia and after a long battle, assisted by Sonic, Dark Gaia appears to be defeated. Instead, however, it reaches full maturity and becomes Perfect Dark Gaia. Seeing the level of the threat, Sonic uses the recharged Chaos Emeralds to become Super Sonic, and with him and the Gaia Colossus working together, Perfect Dark Gaia is defeated and sealed back in the planets core.
In the end, as the planet begins to piece itself back together, Chip throws the exhausted Sonic back up to the Earth's surface and allows himself to be resealed within the Earth along with Dark Gaia. When Sonic comes to, he sees Chip lying unconscious on the ground, similar to their meeting, but it turns out to be an illusion as he quickly disappears. However, his necklace remains on the ground. Sonic puts the necklace on as a bracelet as Chip assures him telepathically that he will never forget him, and that he will always be with Sonic, a part of the Earth he treads. Due to his sacrifice it is unknown if he will return in future Sonic games, though it's unlikely