Mutants are the unintentional results and victims of the Chancellors' experiments.
Originally, they were impoverished peasants of Alterac who the Chancellors attempted to infuse with the essence of Xostheron and Akaerna-Sagai with the intent of creating “Others.” However, the Xie bloodline was the only one which could support the essences of those divine idols, and when commoners where experimented on they were transformed into mutants.
Mutants appeared twisted. They were bulky and muscular, but otherwise hideously deformed and barely recognizable as former-humans.
They were used by the Chancellors as guards in the labyrinth below Alterac City, where the Chancellors plotted and performed their twisted machinations. The mutants were given food and shelter for their services.
After the destruction of the palace and its collapse into the labyrinth below, the mutants were left on their own to
eek out a meager existence in the ruined tunnels.
They were lead by Bill Sleeve.
“Don’t mind the mutants, my dear. They might be stupid, but even failed experiments need employment, and we Chancellors have so many menial tasks we need done.”
“What… are they?”
"What are they? Hahahaha! Why, they are the living proof of just how special you are! The Xie bloodline is the only one which can support the essences of our divine idols. Whenever we tried to substitute lesser stock for that purpose, well… you see the results.”