Near to Mount Rydar, an active volcano, lakes filled by glacier meltwater have become deadly corrosive. A large river is sourced from these lakes and cascades over a cliff, leaving a large stone island. Built on the island is a small keep, protected by resistant stone and bronze sheeting.
An alchemist and devil-worshipper abides here.
During construction, the acidic river was diverted, and destroyed most of a forest. Surviving there still is a horribly scarred Treeherd who has a pack of wolves as pets and considers most things pests. Has no empathy.
Mercenaries imported by a particularly uncaring slavers - Rephatian !Grey Ones!
The Bronze Keep
The lab/fortress of the Arch-alchemist. His real headquarters - even more secure then the Crystal Retort.
Another module location.
Additional Ideas (2)
When one first catches sight of one of these worms, one might think that a giant, 3' long sausage came to life. One would be corrected when its mouth opened and revealed its bladelike jaws.
Elbrexian Worms are found only - so far - in the highly acidic waters about Vitriolic Falls. It is generally assumed that they have limited advantages outside that specialized environment, and so are unlikely to thrive elsewere. Adult specimens reach 3-4' in length and up to 6" in diameter. Their flesh is a waxy white, largely from the thick mucus that the creature exudes. The mucus is highly resistent to acids and akaline substances and allows the creature to survive in its dreadfully harsh environment.
The worms are very stupid and hunt using vibration. They will tackle anything they detect, even fellow worms, and so are normally solitary. Flesh is not common where they live, so they will take advantage of any opportunity to get it.
A worms bite is capable of removing a fist-sized gibbet of flesh from it's victim, its teeth shearing even through heavy leather. As their mouths are also exposed to the harsh acids of their environment, the mucus is also present within as well as without. Their saliva is also acidic, but not sufficiently so to provide a combat advantage.
The biggest danger these creatures pose is that their bite will typically breach defences their victims may have in place to protect them. Whether it is a coating of Elbrexian worm mucas, or acid-proof clothing, the hole caused by the bite may allow for lethal injury from the acid.
This walking cyprus tree bears terrible scars where its bark was scored by acid. He lives in the large wooded area astride the most likely route to Vitriolic falls.
Whatever warmth or empathy this treeherd might have had was destroyed by his injuries and seeing fully two thirds of his treasures forests killed by acidic waters. He does not know that the destruction was artificial - the result of the acid-laden Anur river being diverted to allow for the construction of the Bronze Keep. If he found out, he would take all measures possible to destroy the keep, possibly enlisting the help of the nearby mountain Giant tribes.
This fellow is very similar to # 2 Haun the Burning in echomirage's most excellent 30 Treeman submission.