A mind flayer has called for a massive conference of monsters in the Underdark beneath Hillsfar. Trolls, umber hulks, demons, and more have answered the illithid's call. To infiltrate this gruesome menagerie, you must embrace the monster within yourself.

Hellgate keep - a name that once made the boldest of heroes shudder in fear - was long ago known as the fair citadel of Ascalhorn, a haven for elves and humans. The the demonic horde of bateezu and tanar`ri destroyd all remnants of real cicilization and turnet it into a den of malevolence. Today, the citadel lies ruined. The mistmaster and the harpers destroyed the keep and ended its centuries-long reign of evil...or so they believed

A monastic community of elves and orcs worshipping a divine daughter of both Corellon and Gruumsh tried to bring peace and reconciliation between the two races. For their trouble, they were wiped out by zealots and erased from history. Centuries later, their mountaintop temple is rediscovered -- and rumor has it that two artifacts hearkening back to the very origin of elvenkind and orcdom are concealed within....

This adventure takes place in the Moonsea of Faerûn. The players have been brought to Melvaunt to search for the missing scions of the city's great families. To the north, in Thar the orc tribes converge on the ruined fortress of Xul-Jarak, flocking to the banner of a charismatic warlord. There, he intends to sacrifice the scions of the great families of Melvaunt in a bloodritual to Gruumsh. The players will escape Melvaunt, search along the wilderness of Thar for the Fortress of Xul-Jarak, and then explore the dungeons of the ruined fortress and hopefully rescue the scions before they are sacrificed. There also is a Web Enhancement by Eric Cagle on the archives of wizards of the coast's website designed to scale the adventure to level 8. For example, it replaces the Owlbear with a Tyrannosaurus. This is an easy to scale adventure with much of the player's difficulty coming from intelligently avoiding problems, choosing how to approach each floor in the most tactical way, and quickly adjusting when something goes wrong. The adventure has sidebars including common orc battle cries (In Orc!), ready to use orc names, weather and random encounter table in Thar, a description of what happens if the party fails or partially succeeds, and suggested minis for each of the encounters. There is even an extended description of the bloodspear ritual, an event the party is not meant to encounter in a normal run. The appendix is detailed for all the humanoid characters including the scions and their equipment, the named villains, and variety of unnamed orcs the party will encounter. The fortress also offers an opportunity to introduce the players to the Underdark and the Zhentil Keep. There is a passage to the Underdark the players can accidentally explore, and return to later. Emissaries from Zhentil Keep have come to watch the ritual and have their own motivations. These npcs provide an opportunity for exposition and role playing at a point which otherwise might be combat heavy, acting as a valve for the first floor - helping or hurting the party with subtle magic should the difficulty be off.