The Upstarts is the self-titled name given to a group of hedonistic young mutants. These disaffected young adults of power and wealth collectively felt that it would be a good idea to play a game among themselves, competing for power by killing other mutants. They contacted the powerful telepath known only as the Gamesmaster to act as referee, and he oversaw and monitored the Upstarts' activities.
The individual members of the Upstarts, beginning with Trevor Fitzroy, started several confrontations with the mutant groups Hellions and X-Men. Fitzroy, in particular, was able to slaughter the Emma Frost’s Hellions and nearly killed Frost herself before being stopped by Bishop and the X-Men. Other attempts by Fitzroy included an attempt on the lives of Forge and Mystique.
The Upstarts later began a campaign called the “Younghunt,” an attempt to capture several young heroes from the teams X-Force and the New Warriors. The captives were brought to the Gamesmaster's base in the Swiss Alps. Their teammates attempted to rescue them, only to be defeated by the Gamesmaster, who possessed the bodies of the mutants by using his telepathic ability to control others for the first time. The Gamesmaster was challenged directly by the mutant Paige Guthrie (later known as Husk), who argued that a greater game would be to compete with Charles Xavier and others like him who hoped to find and guide the next generation of mutants. The Gamesmaster agreed and allowed the heroes to leave. This also proved to be last activity the Upstarts would perform as a group.