From the introduction:
Innumerable ages ago, the mortal Valofax set out on a quest for revenge against the demon gods of the underworld. He sought to slay a specific group of ruling demons in retribution for their unholy crimes against the world. A seemingly impossible feat. Defying all conceivable odds and fate itself, Valofax through sheer force of will was successful, earning the admiration of mortals and immortals alike. The gods of light granted him divine power and over the course his endeavor, Valofax ascended to demigodhood. Despite his godlike status, he did eventually die and was laid to rest in a tomb alongside his most prized personal effects. As well as an immense treasure horde, the spoils from his crusade against demonkind, a testament to his awesome achievements.