Madstone

According to the Book:

Something terrible occurred deep in the heart of the Icewood shortly after humans first settled the area. In these cold, northern woods, one of the first humans to carry the Mark of Sentinel ventured into the grip of the Icewood and never came back out. It is said that he came upon a strange, burning crystal that had erupted from the ground and glowed with a midnight-blue light. When the dragonmarked human touched the grapefruitsized dragonshard, he was pulled into its depths, where he remains to this day. Or so the legend goes.
Today, travelers give one portion of the Icewood a wide berth, for the weird Khyber dragonshard called the Madstone has demonstrated a hunger that has called many unfortunates to it over the centuries. The Madstone has now grown to the size of a large boulder, and it seems to get larger with every victim it captures within its dark, crystalline embrace. The expanding shard continues to call others to join it; whether cajoled, tricked, or mesmerized, hundreds of hapless souls have been drawn into the Madstone, feeding it, making it grow, and stirring their minds into the jumbled consciousnesses that have merged in madness within the midnight-blue crystal.

Quests:

Type

Forest