Mark Kent, like his older brother, Clark, was born with superhuman abilities. It was evident by their physical features that they weren't the biological sons of Martha and Jonathan Kent, however, the two did not expect to hear that they were aliens from another planet. However, as the two grew older, Mark started noticing the differences between him and his brother, not just in appearance but in the way their bodies began changing with their powers. He realizes that he is growing stronger than his older brother, yet he is still seen as inferior. This angers Mark, causing him to feel both jealous and insecure. This all culminates in Mark attempting to break free of his brother's shadow. As for how far he will go, only time will tell.