Everett Thomas grew up as a straight-A student in St. Louis, Missouri before his mutant power first emerged. Soon after, Thomas was kidnapped by the techno-organic alien race the Phalanx, who were attempting to learn how to assimilate mutants into their collective, and had captured numerous young mutants. Thomas and his fellow captives were rescued thanks to the efforts of the team of superhuman mutant adventurers the X-Men. After their rescue, Thomas and the other young mutants became the founding members of Generation X, a new team of mutants enrolled in Xavier’s Xavier's School for Gifted Youngsters at the School’s branch in the re-opened Massachusetts Academy. Thomas was codenamed Synch as a result of his mutant ability.
Synch quickly became popular with his teammates, and formed particularly close bonds toJubilee and Skin, and later with M. Eager to learn more about his powers, he spent his time at the academy pushing himself as far as he could go, and often annoyed the others by using their powers better than they themselves could. Soon after, the team was attacked by the energy vampire known as Emplate, who transformed Synch into a creature like him that was forced to feed on the bone marrow of mutants for survival. Emplate teleported Synch to his home in St. Louis, where he attempted to turn his family into creatures like himself and Emplate. He was freed of Emplate’s influence by a combination of his own reluctance to bring harm to people he loves, and the assistance of his teammates Husk, M, and Jubilee.
Later, after Adrienne Frost, elder sister of Generation X’s former headmistress Emma Frost, incited a riot at the school, Synch sacrificed his life to save the students by attempting to disarm a bomb Adrienne had planted that subsequently exploded.
Recently, Synch was revived with an alien techno organic virus.