Apart from a few chance encounters at official banquets, Geralt had the occasion to meet and speak more extensively with this sorcerer on Thanedd Island, during the bloody coup, when all manner of mages jumped at each others' throats and their Council and Conclave ceased to exist. Dethmold and his brother Drithelm, both in the service of King Esterad of Kovir at the time, attempted to remain neutral as events unfolded. To no avail, however, as those who had allied themselves with Nilfgaard thought nothing of the impartiality of others, and many mages simply perished, brought down in fanciful ways by their colleagues' spells or pierced by the arrows of the Scoia'tael summoned to the island by the plotters. Drithelm met just such a fate, while Dethmold saved himself by fleeing.

Dethmold then filled the opening for a sorcerer-advisor at the court of King Henselt of Kaedwen, and proceeded to place all of his abilities at the monarch's disposal.