The creature that attacks D in Twin-Shadowed Knight and the others in the observation chamber in the facility. Machinery there creates a glowing form out of light from infinite energy within the facility. The face of "The Master of the Chamber " can be seen in that light. The light is filled with enough destructive energy to overwhelm the defensive systems of the Fake D's body. The light actually takes the form of the person in the chamber, although mad old Neer believes it to be a God of his own creation.
The creature has no true form as it is an abstract being and takes the form of the thoughts of Neer or anyone surrounding it. It is surrounded by white flames from the endless amount of energy it absorbs.