Late in the Horgon Era, Malmus explorers made the climb up Lirhazi Cavity, an incredible feat given that it is five miles across and two miles straight up. It was named Melgrinn after the first of the climbers to make it over the top - which turned the effort into a sick game of betting on who would make it and one of personal honor for some of the mostly troglodyte climbers. Years later, a fomorian in Malmus's Foreign Affairs division claimed he was behind this contest to the top. Malmus being a sinister empire, this individual was not punished, but promoted. A couple years later, other explorers located passages leading up from Onvorn to the surface region Lands of Purity. By the start of the First Epoch, raiders were attacking the outlying settlements and mining camps of Guthnimor and then those of Hanthaerion. Malmus built the settlement Ygasalax to support these raiders and to profit from them. This city is perched on the upper northern rim of Lirhazi Cavity.
Ygasalax has a series of lifts that connect Ygasalax to the dark reaches two miles down from it. Travelling to the bottom, puts you in sector Kydell of the region Onvorn. There have been enough "accidents" on these lifts that important Malmus personages often use them only in disguise.