Analysis: The first version of the Zero virus to be known was the Sigma Virus which turned Reploids into
Mavericks. Although it was the first known, it wasn't the original virus. The virus
originated from Zero's DNA, therefore the Zero Virus was the original virus. At the time Sigma
fought with Zero, the virus Zero was carrying was transfered to Sigma. Since it caused Zero
to malfunction one would assume the virus in Zero at that time was corrupt or incomplete for
reasons unknown. Once in Sigma the virus melded with him becoming a permanent part of him.
The Zero Virus was first introduced in Megaman X5 when Sigma combined
the Sigma Virus with the Colony Virus he had Dynamo set up. The act of combining another
virus to his own to make the Zero Virus suggests the above was true and that the virus
Sigma got was the incomplete Zero Virus. Sigma produced the Zero Virus on as massive
a scale as he could to get a large amount of the Zero Virus to infect Zero and restore
him to his "true self". In Megaman X6 a new Virus was introduced, this was the "Nightmare".
The Nightmare was an artificial virus which is carried by "Nightmares" that Gate created.
The purpose of the Nightmare was to control the reploids that it infected. It rewrote the
infected Reploid's DNA and AI programs, and sometimes killed them. The Nightmare also was capable
of surviving even if the infected reploid died. The Nightmare, was created from
Zero's DNA, and is either an exact copy of the Zero Virus, but renamed, or is a slightly different
version of it like the Sigma Virus was. This therefore explains how the Zero and Sigma
Viruses worked. For example, when Sigma's body is destroyed he lives on because his true form is
the Sigma Virus, also he is able to control the reploids that he infects(turns into Mavericks)
and uses them for his purposes.
Credits & Copyrights
Mega Man, Zero and all related characters are registered trademarks of Capcom Co., Ltd. Pretty much everything else, except the midis which I didn't make, by me ©2002/2003/2004