So, as a lot of you should know from my occasional mentions of it, some years ago I ran a Hunter: The Vigil LARP. It lasted a couple of years and shared continuity with a Promethean: The Created game I ran some years ago and the Vampire: The Requiem game I've been running (which has just had to go on hiatus, which I'll explain later). For this LARP, I invented three new Hunter organizations to be part of my setting (two of which appeared in play, and the third I just liked having on the shelf but never got around to do anything with), and sometime after the LARP wrapped up I posted write-ups for the groups.
With the World of Darkness Second Edition renaissance going on, I've decided to dig up that old material, give it a quick once-over, and mechanically update it to the second edition rules (or at least to the rules patch in Mortal Remains). This is entirely unofficial and should be considered entirely fan-material unless someone with the authority to do so says otherwise (though I'm 99% sure that by posting it all I'm probably ruling it out as strictly canon, but eh). That said, feel free to swipe, fold, spindle, mutilate, and put to use in your own games.
Also, a note: While this is updated to the Mortal Remains supplement, it also incorporates systems from Compacts and Conspiracies. Neither book is strictly necessary as long as you're at least covered with the Hunter core and the GMC rules update. That said, Mortal Remains is an amazing read. Compacts and Conspiracies has its weak spots, but all in all it also has a lot of interesting and inspiring material.
Every part of the World of Darkness has its quirks, it seems. Every place has some magical fungus, strange vampiric bloodline or portal to the unknown that is unique to it but unknown to everyone else. The Appalachian Mountain Range has its own quirk that influences supernatural life up and down the collection of ancient mountains. It is an entity that slumbers beneath the mountains that lets its corrupting influence push towards the surface. It's commonly known as 'The Mountain God' or some variant on that name. It's been worshipped, studied, feared and opposed by a variety of spiritually-aware groups for as long as humanity has lived within the region.
The Mountain God doesn't show any conscious desire beyond expanding towards the surface. Its energies affect and alter spirits, subtly (at first) tainting them with its resonance like a light dusting of spiritual radiation. It forces its way to the surface through sites of power that often double as weak spots between this world and assorted others. It's been known to mutate wildlife, raise corpses as zombies and fuel all manner of corruptive and destructive magics -- all tinged with a dirty, sulfuric yellow glow or mist. But because it either lacks awareness or interest in what is done with its power, it rarely takes direct action.
The current organized effort against it is known as the Mountain Line Preservation Society. The natural ley lines that criss-cross the region shift and move in a semi-regular cycle and the entity's power can only truly be brought to bear when the lines are in a particular configuration. Since their formation, the Society has maintained a duty to prevent the region's ley lines from aligning in the Mountain God's favor. They have devised simple rituals to do so and a communications network among various chapters to keep tabs on what is going on all over the region.
The Society formed during the Civil War, when occultists living in what is now West Virginia realized that their counterparts in the Confederacy had found a way to organize controlled releases of the Mountain God's power for their own purposes. They began movements, both political and otherwise, to try and cut off that sort of access. They influenced the Wheeling Convention that ultimately divided the state of Virginia in 1863 in a successful attempt to deny the South access to enough sites to gain an edge. They also partially arranged for Francis Pierpont (an associate of the Society) to have control of Virginia after the war to continue those efforts.
After the war there was a government-sponsored spread in education. Many of these early occultists were educators themselves and established the Society as a small historical foundation that exists almost solely on paper. Through political contacts of the day, they arranged for the nascent organization to receive a portion of the government's public education funding that they still enjoy today.
Since then, the organization has operated through the universities and colleges of the region. Every decently-sized campus across the various states hosts a chapter, and it's believed that more than a few schools founded in the years after the Civil War were deliberately placed close to sites where the Society could disrupt the Mountain God's power. They operate primarily through these institutions, sometimes promoting their schools' influence in their communities to give themselves greater access to the world around them. Their political influence has faded over the last 150 years but their localized focus has prevented this from being a liability.
Their methods have evolved over time, especially by drawing on their access to academics (particularly engineers). In addition to the regular performance of ley line-disrupting rituals and the extermination of those willing to draw on the Mountain God's energies, they've developed special technology that gives them an edge. They can track beings influenced or empowered by the energies as well as interfere with the spirits of the region due to the resonance that has infected them. Most of them are instructors at the universities that unknowingly host their chapters and more than a few of the rest began as students at those same schools who unintentionally received an education in the supernatural.
The Mountain Line Preservation Society has mostly avoided the notice of larger hunter organizations but individual chapters sometimes reach out to other compacts such as the Loyalists of Thule or the Union for information or to request necessary assistance to deal with a threat. Individual chapters tend to run to one of two extremes: cagey and secretive, withholding everything about their group but a name; or gregarious and open, sometimes actually contracting and compensating other hunter groups for their assistance in combatting the Mountain God's followers. The openness has caused a minor divide within the Society, as the older members see more strength in secrecy but younger members argue that in this modern age it's easier to control the flow of information than deny it altogether. For a number of years, the original chapter in Morgantown operated as a publicly-known historical foundation and despite the temporary extermination of the chapter (for reasons unrelated to the publicity) it still serves as an example used to prove that such a model could work.