Emma Frost is a fictional character in the Marvel Comics universe, first appearing in The X-Men series. She is known as a powerful mutant with the ability to read and control minds, as well as transform her body into diamond, granting her enhanced durability. Initially introduced as a villain, she later becomes a member of the X-Men and serves as a mentor to younger mutants. Frost is often depicted as a complex character, balancing her past as a member of the Hellfire Club with her role in the X-Men. Her intelligence, strategic thinking, and strong personality make her a significant figure in the X-Men storyline, contributing to themes of redemption and acceptance.