Greg Seymour was one of the original founders of Purgatory in 1985, a band that later changed its' name to Iced Earth. He even was in that line-up that, under the name "The Rose", merely was a bunch of highschool students jamming out, previously to Purgatory.
He accompanied Jon Schaffer to Tampa, and together they slept in abandoned houses and Jons car while they were searching for an apartment for themselves and the rest of the band. After they found one, the rest of the band followed but soon went back home, as they couldn't make it alone.
Greg stayed with Jon and helped him putting together a new line-up of Purgatory. He played on all Purgatory demos. He also recorded the 'Enter the Realm' demo with Iced Earth, but left the band shortly afterwards in 1989 due to personal problems with Jon. Mike McGill took his place.