Pool (Deceit)

Pool was a gestalt being. It was created by a research team for the Spinward Corporation, on a space station orbiting Arcadia. The genesis was the linking of 6 of the senior scientists' brains to form a unified mind. Over the centuries, more minds were added until it essentially became an organic supercomputer. Pool had discovered block transfer computation, enabling it to alter physical reality in the area. It wanted to create its own universe of pure thought, which would have destroyed the Arcadian system. The Seventh Doctor managed to trick Pool into transferring itself into the Zero Room's Tertiary Control Console. He then ejected it into the Time Vortex. (PROSE: Deceit)

Pool merged with other beings abandoned in the Time Vortex. When the Time Lords sent Chris Cwej into the bottle universe, they unintentionally created a gap through which the merged entity invaded the bottle universe's operating system, where it was known as the Horror. (PROSE: Dead Romance)