Based on the Advanced Dungeons & Dragons adventure Ghost Tower of Inverness by Allan Hammack, Demon Tower of Madness is for characters level 5-7.
From the publishers website:
"One of the most grand and terrible of all man's creations is the Soul Gem. Now time grows short, as the madman Zaraffin uses the Gem to summon his unstoppable Nefarian army, almost leveling the region in the process. The Demon Tower of Madness was used as the official 2003 HackMaster World Championship tournament adventure. Non-stop action from start to finish, destroy the gem before it and its minions turn Garweeze Wurld into the Abyss on earth.
A HackMaster adventure for 5-8 characters between levels 5-7, the greatly expanded Demon Tower of Madness (more than twice the length of the original!) offers over 70 separate encounters spread across four rounds. Each round can be played as a separate tournament adventure, or can be used in an ongoing campaign. Unique traps and monsters haunt every twist, turn and dead end of this fantastic adventure. Only the most cunning and resourceful PCs will escape with their lives and their sanity intact!"