Lorelei was a native of the Savage Land whom Magneto transformed into a super-powered being using his advanced technology.
When the X-Men first encountered the Savage Land Mutates, she used her power to hypnotize all the male members of the X-Men, leaving Marvel Girl free. Telekinetically opening Cyclops' visor, Jean Grey was able to destroy the mutating machine, causing all the Mutates to revert back to their former primitive selves, sans powers.
The machine was later repaired and the Savage Land Mutates returned, powers intact, to battle the Avengers. During this clash, Lorelei discovered that her power does not affect artificial beings, such as the Vision.
Lorelei was later recruited by Magneto to join an updated version of his Brotherhood of Evil Mutants. During a clash with the Defenders, Magneto and the Brotherhood were reverted to infancy by Alpha, the Ultimate Mutant.
After this defeat, the Brotherhood disbanded and Lorelei wasn't seen for some time. She later resurfaced in the Savage Land as a servant of the High Technician, an evil scientist who sought to rule the Savage Land using mutated dinosaur-men. In the ensuing battle with the hero Captain America and his allies, Lorelei was rendered unconscious by the Captain's ally Diamondback.