The compound GYX-5 was created by PetraDyne in 1989 using mud originally discovered outside of Millennium City in 1886 by a farmer who noted that some of his fields were incredibly fertile and yielded huge crops that were also extremely resistant to blights.
This mud has miraculous, unparalleled mineral properties and unique rejuvenative qualities. After the healing effects of the mud were originally discovered, the fields were bought by G. Finneas Wurtz, a German business man traveling in America, who built the Dearborn Fields Rejuvenative Bath & Spa on the location. The resort like Spa did a steady trade, but was put out of business during the Great Depression, leaving the site a dilapidated ruin by 1987, and its title lapsed back into the public domain.
In 1987 a college biology field trip to the area resulted in a young would-be biochemist, Paul Storgath, taking several soil samples for a class project. Studying the various samples later he noticed that while handling the soil from the Spa site, an abrasion on his finger stopped hurting and in fact seemed to partially heal before his eyes. Intrigued he ran a number of tests on the soil and returned to the site for a larger sample. He discovered that the mud had incredible bio enhancing effects. He took this information to PetraDyne Chemicals, securing a future there after graduation in return for his findings.
PetraDyne questioned the results at first, but their own research indicated Storgath's findings were correct. Moving quickly to acquire the plot from the state for a pittance, they immediately built a facility on-site and conducted thorough research on how to use this material. GYX-5 was but one of many compounds created by combining trace amounts of the mud with a wide range of other pharmaceutical products. GYX-5 was intended primarily to grow/produce synthetic skin that is indistinguishable from real skin to treat burn victims.
However, Mr. Roboto got its hands on some of the compound and quickly developed a process to grow pigmented skin with hair follicles and natural blemishes by splicing in DNA from a living person, and it was this breakthrough that enables Mr. Roboto's replicants to look real.
However, some of the other benefits of the mud included use in bio enhancements designed to grant superhuman capabilities, and topical creams that that can heal just about any dermatological problem. In late 2005 PetraDyne decided to dig up all of the remaining mud from the site and transport large lots of it to various other PetraDyne facilities around the country so that further ranging research could be conducted and to ensure that they had total control over the miracle substance.
Chemo has a special interest in bio enhancing chemicals and compounds, and took the opportunity to seize control of the miracle material via hired super villains and minions while it was en route to its various destinations. Unbeknownst to Chemo, this made him a new enemy in the form of Mr. Roboto, who needs more GYX-5 to continue to produce life-like replicants.