A servant of the Black Guardian, the Shadow had waited for the Key to Time "since eternity began" and would easily wait a thousand more years if he needed to. His desire to possess the Key to Time for his master seems to be the only thing he lives for. The Shadow keeps his form hidden under a black cloak, similar to the cloaks worn by his servants. These servants, the Mutes, are little more than heavies, doing the Shadow's bidding and ambushing the people that he wants brought to his lair.
The Shadow resides on a "planet" between Atrios and Zeos, although it looks more like a sort of space station. How the Shadow keeps his lair hidden is unknown - the planet may absorb all light or energy, but this is only a theory. Travel to and from the Shadow's lair is accomplished by means of transmats, although apparently only the Mutes know how to operate them to get to the hidden planet.
From his planet, the Shadow has been controlling the war between Atrios and Zeos. He installed a communication device that resembles a skull behind a two-way mirror in the Atrion control room, and he uses it to control the Marshal's mind and dictate his actions. On Zeos, the Shadow forced Time Lord Drax to build a war computer called Mentalis that attacks and defends with great precision.
The Shadow can control people through the use of small black control devices, with a green light at one end, that are attached to the side of the neck. They can be easily removed by anyone who spots them, so they pose little physical danger to the person being controlled. The Shadow also has a cage in his lair, with two doors made of interlacing metal bars and a comfy chair in the center. When the doors are closed, the Shadow can use the cage as a torture device, causing some form of energy to crackle between the bars if the prisoner lies to him.
