Everett Thomas was born in St. Louis, Missouri. He was first introduced in X-Men #36, when the mechanical collective race known as the Phalanx had assimilated the X-Men and attempted to wipe out what was to be the next generation of mutant heroes (Husk, Jubilee, Monet, and Blink, all except Blink future members of Generation X). Synch had accidentally synched to Banshee, who was in the area, and had shattered all the windows in his area with Banshee's "borrowed" scream. He didn't know how he did it, but the next thing he knew there were a slew of police officers with guns pointed at him. Unfortunately for them, the menace wasn't Everett, but the Phalanx, who attacked the officers.
Luckily, he was saved thanks to the help of the White Queen, Sabretooth, Banshee, and Jubilee. This misfit band of heroes ended up saving the other kids who were attacked by the Phalanx, and from the sacrifice of Blink, they escaped the menace. Following this, the kids were all relocated to the Massachusetts Academy, where they would train to use their powers, receive a formal education, and act as Generation X, the next generation of X-Men, on the side. Everett, along with M, was one of the foremost students.
When Emma Frost's sister, Adrienne, came to America, she forced Emma to re-admit her back into the school. If not, Adrienne would release information to the parents of the normal kids that the Xavier School For Gifted Youngsters was a secret training ground for mutants. Later, Adrienne created mutant hatred amongst the human students in the school. When the parents of the non-mutant students heard that their children were going to school with mutants, they all arrived together to take their children away from the academy. However, Adrienne Frost had planted bombs all around the school. Banshee and Synch set out to turn off and deactivate all the bombs, while Emma and Adrienne brutally fought. Eventually, Emma pulled out a gun and shot Adrienne.
Meanwhile, Banshee and Synch separated. Synch found a bomb and there were human students nearby. So, he "synched" with the nearest mutant, who was Monet. However, Monet was too far away, so he only received a portion of her powers, which happened to be her super strength. Using all his might, he threw the human kids out of the room, saving them from the explosion. Sadly, he wasn't able to save himself, dying to save his human peers.