| Category | Valleys |
| Continent | Brucrumus |
| Region | Grashakh |
| Map | Mauhúl Valley |
The Mauhúl valley is dotted with ancient ruins from a time when angels and their mortal allies battled an Abyssal invasion. This Demon Spawn War (89 GE - 269 GE) saw the valley hold high strategic importance. Fortifications and Covenant armies blocked demon movements east and west, continuously working Bileddanul's rich Mithril veins. The Covenant forces stationed here were Turkûn serving under then-archangel Naraz-Nâru, battling demon armies led by Ahnuthall, who answered to Orcus. After five years of fierce combat, a specialized Covenant unit deployed to the area, tasked with mitigating their enemy's numerical advantage. This unit, the nascent Blighters, developed the virulent RT-12 Leech disease, which spread through infected plants and wreaked havoc on both sides. Due to its virulence, the valley was ultimately abandoned for the remainder of the war.
Today, Mauhúl is a disease-afflicted realm, a place of illness and deterioration, where only the most resilient of flora and fauna may endure. The native creatures of Mauhúl are of the Dire variety, primeval in aspect, and frequently exceedingly aggressive in temperament.