Ancient (Sonic the Hedgehog)

The Ancients are an alien race from a now destory planet. They are an advanced ancient extraterrestials that existed since the Prehistoric age. Their original homeworld was destroyed by a malevolent entity named The End, which forced them to find a new home on Earth. They settled in the Starfall Islands and harnessed the power of the Chaos Emeralds to build robotic machines known as the Titans. By the time The End arrived on Earth and attacked the islands, the Ancients used the Titans to fight against it. However, The End is too powerful for the Ancients to defeat, even with the Titans, so one of them piloting the Titan Supreme harnassed The End, sacrificing himself in the process, which gave the other ancients time to imprison The End into Cyberspace. The remaining Ancients flee the Starfall Islands, but not without getting the Chaos Emeralds away from The End's grasp and brought them to the Master Emerald.

By the time of the series events, the Ancients went extinct, but not before uploading their souls in their lucky charms, now known as Koco. It is later revealed in Dr. Eggman's research, the Ancients are the ancestors of Chaos and the Chao.

Appearance
The Ancients are very similar to their descendant Chaos, being humanoid beings with a long body made of plasmic substance, they also have sharp claws like hands, two long protrusions at the back of their head and have two bright eyes. Usually they don't wear any clothing, but in their torso, they have Kocos as their lucky charms.

Culture and Society
The Ancients are extremely intelligent, with such advanced technology than modern-day technology. They created Cyber Space which stored all the Ancients' hopes, dreams, memories and data and they can be accessed through portals. They also created advanced weaponry such as the Titans, towers and an army of robots in order to defend themselves against The End, who wants to annihilate the universe.

In the DLC The Final Horizon, it is revealed that the Ancients worshipped a god, as the symbol that appears in the sky is the representation of said deity.