Derelion is an Eladrin town founded hundreds of years ago (when humans first founded Geoff) located in the Dim Forest. Prior to that, the Eladrin had simply roamed through the forest, but saw the need for a centralized trading post with the arriving human civilizations, who would not be allowed free access throughout the rest of the forest.
The Eladrin that lived here survived by hunting, gathering fruits and nuts, and producing trade items such as clothing, woodworkings and arrows.
It was built to look like natural trees, and this was done so skillfully that from some directions it is possible to pass within a dozen yards of the town and not realize it. Had it been disguised from the air as well, it might stand as a refugee even today.
The Eladrin were not caught unaware of the Giant Invasion of 583 CY; their scouts had reported the approach of hill giants and ogres nearly a day before they were expected to reach town. Advance parties were sent out to harry the invaders with arrows while those in town prepared defense-works and sniper positions.
They were aided by a human wizard named Faffle, who used his magic to hide key groups of Eladrin and reinforce the town’s defenses. When the giants and ogres reached town, they suffered a hail of arrows from the Eladrin and charged ahead in order to close the distance as quickly as possible. Faffle then cast a Summon Shadow spell to take down the charging giants, but instead of four shadows, he accidentally summoned forth Hasforenses, a shadow dragon that happened to be passing through the equivalent spot on the Demiplane of Shadow.
To the horror of Faffle, the Eladrin, and their charging enemies, Hasforenses, promptly set about blasting everyone around her with spells, breath attacks, claws, tail, and bite. It was a disaster for all. Entire groups of ogres, giants and eladrin, engaged in their own stuggles, failed to notice that the dragon was present until it was too late.
While good and evil forces battled each other, she picked off strays and added to the chaos. When the combat was over, dead and unconscious bodies lay strewn everywhere, the shadowy dragon silently triumphant. All of the giants and ogres were dead and the few surviving eladrin were put to flight.
In the eight years since, any giant, ogre or eladrin that dares to venture too close to Derelion simply never return. The area is currently avoided by all.