Mighty Jagrafess of the Holy Hadrojassic Maxarodenfoe

Biology
The Jagrafess was a gigantic, gelatinous creature similar to a slug in shape. Its exact origins are not known, but it was sentient and able to communicate in a series of growls and screeches. It had a life span of about three thousand years, with sharp, vicious teeth and several vestigial eyes. Its metabolic rate, however, meant that it had to be kept at low temperatures to survive.

Biography
The Jagrafess was an ancient, enormous, mauve monster, full of heat, fat, muscle and water. It had to stay cool to live. It was put in charge of the ersatz Fourth Great and Bountiful Human Empire in the year 199,909. Away from its home planet, only a facility like Satellite Five could produce enough cold air to sustain it. If no cold air was supplied, the Jagrafess would overheat and explode spectacularly. The heat from Floor 500,where the Jagrafess was installed, was channelled away to the rest of the station, allowing the Jagrafess to remain in a cool climate. Realising this irregularity, Cathica Santini Khadeni used her infospike to channel the heat back towards Floor 500, killing it.

The Ninth Doctor discovered the Fourth Great and Bountiful Human Empire was being controlled by the Jagrafess in 200,000, via the news-broadcasting space station Satellite Five, located in Earth orbit.

Since the Jagrafess could not operate Satellite Five's controls, a human known only as the Editor carried out its orders. (DW: The Long Game)

The Jagrafess itself was a pawn of the Daleks, part of a stratagem spanning several hundred years. After its death, the Daleks went on to other stratagems and renamed the Satellite the Game Station. (DW: The Parting of the Ways)

The Doctor would later compare the media being in control of Arkannis Major to "the thing on Satellite Five", not remembering the Jagrafess' name. (NSA: The Stealers of Dreams) The Jagrafess was later mentioned by the Eleventh Doctor. (NSA: The Silent Stars Go By)