Amy was a young mutant imprisoned in the Red Skull's concentration camp in Genosha. She had the ability to create illusions, which were actually real constructs made from fragments of her imagination or those near her. When Magneto arrived in Genosha to investigate the situation, he freed Amy from her inhibitor collar. Once Magneto was found and attacked by the S-Men, Amy tried to help him, but he told her not to risk her life nad leave him.
After the Red Skull was defeated, Magneto returned to Genosha to turn the island into a mutant sanctuary once again. Amy was one of the numerous mutants hiding on the island. Amy's powers had been affected by the horrendous experience of the Skull's concentration camps, and the constructs she created ended up becoming monstrosities. She accidentally unleashed a construct of Herr Hitzig, a Nazi soldier Magneto feared when he was a prisoner in the concentration camps during the Holocaust.
The construct began a series of murders, and Magento finally realized the true nature of Amy's abilities. He confronted Amy, who was in the far reaches of Genosha. Because the only way to stop Hitzig was either for Magneto or Amy to die, and because of the experiences in the Skull's camps were haunting her, Amy embraced her fate, and let Magneto kill her.
Powers and Abilities
Mirage Solidification: Amy had the ability to project illusions based off her own or other people's imaginations and memories. Her ability could do and became so much more than mere phantasms conjured by simple thought processes, but her psyche was tainted when the Red Onslaught came to be and her living illusions steadily became decayed, rotting into grotesque nightmares made real; given life by her own tortured psyche or that of others.