Lone Modron

The "Lone Modron" is a nonaton modron. 200 years before the invasion of Sigil, he began to suspect that the modron god-king Primus was under the influence of some external force and left the modron community in Mechanus. He has traveled extensively throughout the planes.

He was discovered by the Dogs of War hiding in the plane of Limbo. They helped repair some of the damage and disease he had accumulated over time and they decided to call him Zaphod.