Opal is a Fox who couldn't catch a break. After losing her parents in an Eggman attack, she was a smart kid WAY ahead of her classmates and was chastised because of this. It wasn't until people in high places got wind of her vast intellect that she was given the "monumental" opportunity to work for the Esteemed "Dr Ultio Nebulous" for the purposes of bringing "peace" to the world. However, this wasn't as it was made out to be. Opal was tricked into assisting the "good Dr" into finishing his greatest Creation: Metal Surge. Upon discovering this, Opal sabotaged the final prototype and tried to flee, but she couldn't get far before Nebulous found her on her way out. Captured and restrained for the time being, Opal was kept locked up while Nebulous was focused on fixing his Creation ready for a test. It's not until Marshall and Surge come knocking, that paths will be crossed and a team set to protect the multiverse will be formed.