A founding member of the X-Men, a mutant with telepathic and telekinetic powers and the love interest of Cyclops and later his wife. She is both a caring and nurturing person, but also has to deal with being one of the most powerful mutants around and is in a constant struggle to control her powers. An Omega-level mutant, that once she could not control it took on the physical manifestation of the cosmic Phoenix Force or Dark Phoenix.