History
Lazarus is Domino’s younger brother and was brought up in the same facility which was breeding mutants for war, as she was. His “mother” decided that he was too powerful to let live and attempted to kill him, leading to Domino rescuing and leaving him at a church for adoption. It is implied however that after these events his mother still tracked him down and eventually killed him.
Powers
Lazarus’ ability to enhance emotions is so powerful that people can swiftly become addicted to it, leading to them committing suicide during the withdrawal.