In the Greenmounts above Endon, the passes hide a history as long and tumultuous as will be found anywhere in the plains below. The city of Llanybydder, once the trading hub for the dwarvish communities, was itself a conquest by the dwarves from the elves in ages long past, and the dwarves purposefully built a route from Llanybydder to their mines further up the peaks – the winding tunnel of the Byddervein.
When Llanybydder lost its position of trading hub to the cattle town of Shepshed below it, the tunnels through the Byddervein were shut, and have lain abandoned for many decades. In the darkness, new life has flourished in the abandoned tunnels, and any traveller trying to traverse the Byddervein must be prepared for the unexpected.
In its heyday, the Byddervein was one of the more impressive examples of dwarven craftmanship in Endon, and in its centre the Vein itself, a chasm stretching deep into the heart of the mountain. The tunnels were lit with a type of reflective crystal lantern constructed in the smithies at Glaston, and graceful stone bridges arced across the darkness below. Now, the main bridge has fallen due to disrepair, and the props and walls have begun, too, to collapse on themselves.
On Entering the Byddervein
"A steady drip-drip-drip echoes down the stone tunnels, accompanied by a strong, sharp smell - something fungal, something decaying. The dust in the air fills the nostrils and makes it difficult to breathe, as does the abject ruin of the tunnels themselves: half-rotted beams overhead, the clumped mushrooms climbing up the walks and onto what appears to be the huddled bones of some unfortunate miner. And, just on the edge of hearing, a high, irregular clicking noise."
It is not known precisely how deep the Vein itself goes, only that the movement of the dwarves brought something to the surface: something repelled by but curious of the passage and the light, kept at bay while the activity flourished, but now present and waiting in the darkness, enjoying its new territory.
The Fungoid Village
Within the tunnels, since its abandonment, the rocks have been to seep with the moisture of the mountain above it. In times long past, it was this very moisture that carved out the Vein itself, but now provides a warm, damp environment, perfect for fungi.
But not all of the fungi are the trunked mushrooms that cluster against the walls: from the depths of the Vein, in some exodus, a population of N'Qatur came up from the darkness and founded a colony in the abandoned halls. They farm fungi in the quiet tunnels, dug their homes into the trunks of the mushrooms, and enjoy a primitive, quiet life outside of the reach of the Ungol, which is too large to follow them into the tunnels.
The Vein
The Vein in the centre of the tunnels, sometimes called the Chasm, is a deep rent in the earth, a crack in the stone hundreds of feet long and immeasurably deep. While the previous carves of the tunnels had their own mythological explanation for the presence of the Vein, its history is not as significant as its present. It provides some easy access between the surface world and the Underdark far below, and though the N'Qatur have managed to flee into the safety of the tunnels, the Ungol is not far behind - what manner of monster it is in unknown, save for its spiderous form.
But whatever it is is far better trapped within the abandoned halls of the Byddervein than allowed out into the open spaces of the world beyond. While it kept its distance from the hustle and bustle of the miners when they were there, it has had unchallenged domain over the Vein for countless decades, spinning its webs and waiting.
The Cairn to the Ungol. Though the Ungol preys upon them - and upon anything else it may come across - the N'Qatur have learned not too let it become too hungry: they occasionally leave it sacrifices of slaughtered spiders, rodents scurrying through the tunnels, and their own dead.