A hero named Gladmar ventured to the gates of Hell itself in order to get the blessed Ring of Eoervan for King Mithidas. Since his return Gladmar has been haunted by increasingly more horrible dreams. Finally a week ago he went wild and had an insane fit. In the process of subduing him, ten of the palace guard were killed and many more were wounded.

The powerful wizard Dracnard has determined that Gladmar is possessed by the demon Demogorgon. The only way to cure him is to recover a magical golden statue of the demon which was last heard of in the possession of the evil Lord Rovnart hundreds of years ago. His stronghold, the Black Castle of Na'Gog, was conquered over two hundred years ago and all of its inhabitants were killed. The castle was then abandoned because of its evil reputation.

King Mithidas has called for adventurers to seek the Idol of Demogorgon in the Black Castle to cure Gladmar. He offers a reward to the successful hero. However the deed must be done quickly as Gladmar will soon be so completely under the demon's control that he can never be cured.

After riding for many days you see a huge, sinister, black ruin standing stark on the horizon. As you get closer the ruins seem to emanate an aura of ancient evil. The faint road you have been following leads to the smashed front gates.

Details at Eamon Wiki