From the introduction:
Iggwilv’s Legacy is a web-based adventure expanding the former lair and home of the dread archmage. The first part, “Iggwilv’s Horn,” details the history of the archmage’s mountain, its outer slopes and caves, and the lands surrounding it. The second part revisits the clas- sic adventure “The Lost Caverns of Tsojcanth,” updated to use 3.5 Dungeons & Dragons rules. The third part, “The Hollow of the Horn,” explores yet more of the chambers within the mountain’s deadly interior.
“Iggwilv’s Legacy” is designed for a party of four 11th-level characters, but any combination of 10th- to 12th-level characters should suffice. The group mem- bers should possess at least one magic weapon (if not more) and have a spellcaster among them. Given the story’s focus on horror, play runs best with a party of
primarily good-aligned characters, but this is by no means a hard and fast requirement. Indeed, a party of all neutral (or even evil) characters might benefit just as much from exploring the halls and twisting passages of Iggwilv’s Horn and its Lost Caverns.