Esper

 Espers  are engineered humans with advanced mental powers, often used as biological machines, indoctrinated from an early age to serve the Empire, with little or no free will of their own. Some had their brains removed to become esp-blockers, some went to feed Wormboy, and many of the remaining espers either functioned as telepaths, providing FTL communication to distant parts of the Empire, or battle-espers, who would use massive pyrokinetic and telekinetic abilities alongside the Imperial army in battle.

The Esper Underground is led by a group (possibly) of mysterious psychic projections. The Esper Liberation Front is the militant faction within the Esper Underground.