From LEGO Batman Wiki
Although Victor Stone's scientist parents encouraged Victor to pursue academic interests, he found athletic activity far more to his taste. During an experiment, Victor's mother accidentally unleashed a creature from another dimension that killed her instantly and badly wounded Victor. While his wife died, Victor's father managed to save his son by grafting cybernetic parts to Victor's organs and computrizing synthetic nerve bases to his spine.
Now half organic and half molybdenum steel, Victor felt alienated from being no longer able to compete on the athletic field due to his body. However, after meeting and becoming a member of the Titans, Victor has found like-minded teens in similar situations to himself and seeks to guide them away from the alienation he himself once felt. He also later becomes a member of the Justice League.
He can be played in LEGO Batman 2: DC Super Heroes and he has heat vision and magentism. He doesn't need to be bought he only comes along after you beat some levels.