Altairan engineer, noted for creating the underworld of Altair, and possibly the cloning technology to copy the consciousness of a living individual into an artificial form. Hubbald died early on, possibly a few years after the remaining inhabitants of Altair's cataclysm evacuated into the environment beneath.
He took many important secrets to the grave. One by one all the other Altairans died, until eventually only Harlan remained.
Tin Man - Harlan notes that Hubbald was the creator of the life-sustaining underground Altairan environment.