Aducath was a mage who ended up possessed by a spirit from the ancient past.
He first appeared in Andris, in the year of 430, looking for the ingredients for a potion that would cure his sneezing (an affliction that would manifest itself by the summoning of several air elementals). Even though the people in Andris helped finding the materials, the potion did not work as expected, and made the sneezing worse. In spite of that, Aducath did not mind to announce that he was looking for the Black Hand in order to learn from them how to become a powerful wizard. As it happens, the Hand was looking for Aducath as well, but if they ever found him, that was not recorded in the public archives.He was also interested in finding magic stones, an object sought after by many in 430, after Evers announced they could be used to cure Seth. Eventually, he got a magic stone from Morgoth II, a fighter who was hoping he could form an alliance with the strange mage.
Aducath took refuge in Aborek, where he set up his laboratory to experiment with the stone. By that time, he was able to summon fire elementals, but not much more, and his crass ignorance on the Oberin world shocked a hunting party who chanced upon him, as he declared he had no idea who Seth was.
Even though he was considered by most an amateur wizard and a megalomaniac, he was still regarded as a potential threat, and the mercenary Zem Stormbrow was hired to find Aducath's whereabouts in case he got in touch with the Hand. Zem, however, was arrested a few days later by Marali.
Then, the transformation happened. Much to everyone's surprise, Aducath's body was not inhabited by Aducath's soul anymore. Instead, a spirit had possessed him, and was now using his fast decaying body to find the "persecutors" who had wronged him before. The new soul of Aducath did not recognise the current state of the world, and went from town to town attacking the elements of the Vanguards, who he believed were responsible for whatever had happened hundreds of years before.
Aducath was finally killed by a group of adventurers, but his death was not reported, so it is not possible to know what happened to the spirit, nor which was its origin, though some theories were formed. The final document we possess is some pages of Aducath's diary during his time in Aborek. They are collected under the title "Diary of the Fire Maven", and tell of Aducath's struggle to understand the words of Black Magic, as well as of an apparition lurking around his room in the ruins.