The Oracle of Delphius is a mysterious sage that hails from the Sonic Underground dimension. Not a lot is known about him except that he can read futures and pasts. He was the one responsible for telling Queen Aleena the prophesy that resulted in her parting way with her offspring. He was also responsible for telling Sonic, Sonia, and Manic about they’re past resulting in they’re formation of a resistance group against Dr. Robotnik.
The Oracle first made himself known shortly after Dr. Robotnik’s siege of Mobotropolis, altering it into his own city of Robotropolis. He located Queen Aleena, who was hiding with her children after a bounty was placed on their lives. The Oracle foretold her a prophesy in which her offspring’s lives would be lost if she did not separate from them immediately. With a heavy heart, the queen sent her children to three separate guardians. (SSS: #10)
The Oracle would later return once again after Sonic, Sonia, and Manic formed a band with each other, this time looking to the past. He revealed the children their history together as siblings and the children of Aleena. Shortly afterwards the children’s caretakers were roboticized by Dr. Robotnik. This, coupled with the Oracle’s words would spark the hedgehogs to form their resistance against the evil doctor. (SSS: #10)