No Really, We're Sheep
The Underhell is a facet of the near Umbra that dominates the North Eastern portions of Chicago. To reach the Underhell, one must step slightly deeper into the Umbra than the most immediate Realm, which is now dominated by Commerce and Weaver spirits.
The Underhell is a shadow of the Great Chicago Fire of 1871. The Underhell is a wyrmhole that lacks most of the traditional corruption associated with the Taint of the Wyrm. The fire was primarily a manifestation of the Wyrm as destroyer, rather than the Wyrm as corrupter, which is perhaps best embodied by the fact that the Underhell is a realm primarily of Fire spirits rather than Balefire spirits.
Ruled over by a Gaffling known as O’Leary’s Cow, the realm serves as a rejection of the Weaver and it’s stranglehold on the massive city. Any being bent on subverting the callous chrysalis that throttles the Chicago-land area is potentially welcome in the Underhell, provided it can weather the holocaustic climate.
There is a long-going campaign by servitors of the Wyrm to increase the presence of Balefire in the Underhell, seeking to create a full-fledged blight. The influence of O’Leary’s Cow and the hostile nature of the environment have served as a natural buffer to these attempts, to say nothing of the fractious focuses of those who would advance the agenda of the Wyrm, resulting in very slow progress on this project.