According to the latter, the Immortal Alchemist attempted to summon Hadum in Cron Castle during the reign of Agris III. That event led to the destruction of the castle in a massive explosion and the death of the King.
The murals seem to indicate that the alchemist presented Agris a scroll that allowed the ability to summon Hadum, but the ritual where he attempted to do so did not yield the intended immeasurable power for Agris, or at least could not be controlled.
Statues depicting Hadum can be found in Balenos in several locations, for example near the Altar of Agris or north of the Balenos Mountains dividing Serendia and Balenos. There's one in the ridge near the Northern Heidel Quarry, and another near the Serendia Shrine. He also is depicted in statues in the dwellings of the Shadow Knights, followers of Kzarka and Belmorn, in both Serendia and Calpheon.
- While being presented as a major figure in the mythical cosmology of the setting, to the point where even the Ancients knew about the entity, their record is the only source of information about it.