The Thought Robot is a Sentential that woke up in a body of pure thought. He is powered by symmetry, memories, duality, probabilities, and possibilities. A doomsday machine engineered by the Monitors to defend against the ultimate evil. Capable of adapting instantly to counter any future threat. A sentinel-suit designed for a single purpose, to protect all existence against the ultimate enemy. A plot device that constantly adapt itself to defeat any evil.