Mr. Sinister

Mr. Sinister, born Nathaniel Essex, is a Marvel Comics villain known for his obsession with genetic mutation and evolution. Originally a Victorian-era scientist, he was transformed by Apocalypse into a near-immortal being with advanced genetic manipulation abilities. He often conducts experiments on mutants to unlock evolutionary potential and has a deep interest in the genetics of the Summers family. Mr. Sinister is a calculating and cold figure who manipulates others to achieve his goals, frequently operating behind the scenes in mutant affairs.