Famous Battle: Dark Phoenix Saga

Dark Phoenix Saga
The Phoenix Force consumes Jean Grey and with the manipulation of the Hellfire Club's Mastermind she is driven mad. The Phoenix Force becomes the Dark Phoenix and consumes the power of a star and destroys an entire solar system before sacrificing herself to save the universe from mass destruction.
The evil mutant Mastermind seized mental control of Phoenix and released her dark side in a plot to destroy her fellow X-Men. She became murderously uncontrollable. In an escalating wave of destruction, she assumed the identity of Dark Phoenix and annihilated a solar system. The Shi'ar, an alien race, demanded that she be destroyed before she could do more damage. In a battle on the moon, the X-Men sought to defend her from the Shi'ars greatest warriors. Phoenix realized she truly was a menace far too dangerous to live. With a parting word of love to the X-Man Cyclops, she died, the willing victim of one of the battlefield's traps.