The Legacy Virus, contrary to the name, was a viroid and was released by Stryfe, a terrorist (and clone of Cable raised by Apocalypse) from approximately 2,000 years in the future.
If, however, it did detect the X-factor, it would begin inserting introns into the transcription codings of the victim's mutant RNA, the process commonly being triggered after the patient used their powers for the first time after contracting the disease.
[citation needed] Legacy-1 attacked general transcription and replication of all cells, a messy and non-selective process that resulted in a condition akin to a fast-replicating cancer.
Legacy-2 was much closer to Stryfe's original template and more in tune with his desire to stir a species war between non-mutant humans and mutants.
Although all strains of the Legacy Virus were more dangerous than HIV, they shared similar symptoms such as skin lesions, fever, fatigue, and coughing.
[1] In addition, comics featuring the Legacy Virus illustrated the similar social impact of the further isolation of a stigmatized group.
[citation needed] During the X-Cutioner's Song crossover, the villain Stryfe gave Mister Sinister a canister that he claimed contained 2,000 years worth of genetic material from the Summers bloodline.
When Gordon Lefferts, a scientist working for Sinister, opened the canister[2] after Stryfe was apparently killed by Cable, they found nothing inside.
Colossus, who did not want any more people to suffer his sister's fate, snuck into McCoy's lab and injected the cure into himself and activated his mutant powers, transforming his body into organic steel.
The instant cure gave Magneto a vast army overnight and allowed him to begin carrying out his plans for world conquest in the Eve of Destruction crossover.
[9] Listed below in alphabetical order are the characters infected by the Legacy Virus: (Revealed in House of X #2 that she was secretly a mutant, and that the infected Moira was actually a "Shi'Ar golem") The Ultimate Marvel universe version of the Legacy Virus is created by Nick Fury, in an attempt to replicate the Super Soldier experiment that created Captain America, using Beast's blood.
The virus turns normal humans into super-strong beings, but is fatal to mutants, prompting Fury to hold Beast in S.H.I.E.L.D.