So basically, his name is Gear the Fox (not that original, but he's my OC, shut up). He was raised in an orphanage, until he was 6 years old. One day, a man came by, and saw Gear there, and without a second thought, adopted him. He was brought to a lab, where a week later, was injected with nano machines that allow him to generate, and manipulate liquid metal.
the man I mentioned is a doctor studying bio weapons named Dr. Zeon. During Gear's uprising, Zeon's assistant, Maggie wolf, thought Gear could do with a friend, so she brought her daughter, Eliza, to play with Gear, when he wasn't in testing with the doctor. The two became fast friends.
A few years later, on Gear's 10th birthday, there was an accident at the facility. Another experiment had gotten loose, and was rampaging about. Maggie was unfortunate enough to be killed by said creature. In a fit of rage, Gear hunted down this creature throughout the facility. Upon finding it, he noticed that the creature had abilities similar t