Hiero was the son of a couple of adventurers who lived in the island of Matai-Mobi. Both of Hiero's parents being hawks, they had their own natural color palettes and unique ways. It just so turns out that Hiero's mother was the daughter of Ridas who ran away at a young age to enjoy life to its fullest and escape royalty. She met up with a male of the same age from Terre-Tribu. Both loving nature and enjoying the thrills of stirring up trouble, they lived a happy adventurous life. Though, they began to call forth negative attention from Vokama who missed his daughter dearly.
Hiero's mother on the other hand refused to go back to Ridas because she knew she wouldn't be accepted and she hated the royalty. It turns out, her and her partner settled down in Luft-Tribu and after some time gave birth to Hiero. During those days, she and her partner were caught. The two escaped into the ocean, dodging the Igna-Tribu troops along with Ridas. While the couple swam away, Ridas noticed something peculiar in their remains. The peculiar object turned out to be Hiero's egg that nearly hatched. Ridas acted smart and told the troops to send the egg to the nearest care-taking site in hopes that the chick will grow up with no memory of what took place or of where he was born.
Despite the fact that Hiero was a bipowered Hawk, (He could control Earth and Fire) he was only taught one element and never knew about his second element's existence. As for his parents, they are presumed deceased. That is because Matai-Mobi's oceans are considered incredibly deadly from the wildlife that surrounds them. Ridas knew everything about Hiero and his origin, but never told him any of it to keep him quiet from finding out about his original family lineage.
Ridas even changed Hiero's name to Hayden Hiero. Felix, instead of Daniel Sprax like he was intended to be named. He also terminated every bit of information that could be found about Hiero's original life in hopes he would never find out. Ridas even committed suicide by rushing his heart with fire. He did that so that the truth would never get out.
To this date, Hiero will never know the truth of his past and he has scrapped it because he sees it as a waste of time.