| Category | Cults |
| Region | Azrik, Izagunbar, Lands of Purity, |
| Grashakh, Troll Bogs | |
| Headquarters | Agdúrn |
| Size | unknown |
| Race | any |
| Alignment | evil |
| Deity | Rioch Tetrax |
| Purpose | famine, disease, blight |
| Founder | Gúlúrn |
| Established | 15 Bliss 1336 |
Borurthane is one of the largest disease-spreading cults in the realm. The cult was founded in 1336 by Gúlúrn; a Lorhazi sorcerer once holding considerable influence in the Troll Bogs. The cult's libraries at Agdúrn contain the original works of Rioch Tetrax. Gúlúrn recovered these ancient texts from the Spire of Rioch Tetrax and subsequently used them to spread virulent plagues.
Cult members of Borurthane have vast underground farms for harvesting fungi and spores.
Borurthane earn much of their income from mercenary work. In the Coeus Civil War (1694 - 1697), they carried out an operation for Raxcvillibus, spreading plague and sickness in Bithiemeth.
| Cell | Region | Location | Leader |
|---|---|---|---|
| Agadî | Azrik | Merorarg | Ghamúl |
| Ghazul | Grashakh | Dumugon | Azgash |