Welcome to Gaia! ::

This is my own personal opinion and may not exactly match up with the story, but mind you that, since the Gaia (G) Virus was based off of Capcom's trademark T Virus, i think it would be proper to propose that a similar formula would have been adopted in Gaia's hidden background as far as creating multiple strains. Edited sections in bol

G` Strain: Unleashed in October 2004. Created zombies of a generic type if it reacts with dead/decayed tissue. Has curative properties when used in small doses, but that heavily depends on the subject. Was likely the original strain for the "ideal heir" project between Johnny and 247, but Johnny wanted something stronger...

GR Strain: Unleashed in October 2005. Created "Grombies" with the special characteristic of super pale skin, protrusions on one's head, or a full-grown Grunny attached to their head. Said to have originated as a mixture of rabbit blood and G` Strain that inhabited the first host (nicknamed "Lord Grunny") and spread to other test subjects (or perhaps host cloned from prime host). THANKS TO CAPTAIN WICKIT FOR CONTRIBUTING

Giovanni Strain: Discovered in April 2005 and April 2006. Gino and Johnny K. both share this strain which is a heavily augmented form of G`. Johnny K. is a special case, as his genes were mutated to copy the actions of a parasite. Gino's genes were mutated so that he would be the host body of the parasite. The strain might have been temporarily negated by "Gino's" being injected with a foreign substance - X Strain. Very likely was the strain used in the "ideal heir" project between Johnny and 247, but was created by Johnny against the advice of his collaborator in the project.

X Strain: Developed by LabtechX. Released in October 2004 as antidote to the G` Strain, and again in 2005 as antidote to GR Strain. Used in April 2006 to force separation of the two Giovanni-infected Gambinos. May be of the exact same strength as the Giovanni Strain, but an opposite polarity. However, massive doses of X Strain can lead to aggressive and violent psychosis. It is very likely that the X strain does in fact have curative properties and may be the product used to heal the mutilated Santa in 2005 (correct me if i am wrong on that).