So as I've spent a bit more time adapting the Ghost Tower, I am thinking of using the dungeon pretty much as written, but completely redoing the tower part.
Basically, in the original the tower was roughly divided into four levels according to element, with some fun transition scenes between each level involving reverse gravity.
Since the context IMC is more about devils, summoning circles, and goetic theurgy, I am thinking of redesigning the four levels according to four moral challenges/tests of character the wizard designed to safeguard the Soul Gem.
As an aside, since the dungeon below is more of a traditional Old School crawl (if anything can be called traditional about the Ghost Tower!), I'm thinking the 4 rooms of the tower will be more set pieced since that's 4e's strength anyway.
Any cool ideas what I might include?
Some ideas I'm thinking...
Stoppered Bronze Ewers, some kind of puzzle like the grail scene from Indiana Jones where you need to unstop per the right ewer(s), or perhaps transfer spirits between Ewers.
Burning Angel in Magic Circle, this would be a roleplaying challenge with an angel of dubious virtue who seeks to convince PCs to free him, gaining a potential ally within the tower...but leading to complications down the road.
Succubus/Erinyes in a Wishing Well, attempts to lure one or more PCs into some kind of bargain. This would need an impending threat of some kind to make it more interesting and encourage split-second deals with the devil.
Hall of Lingering Spirits, ghosts of apprentice mages & living spells, there would be a logic puzzle to figure out which of the apprentices betrayed their master. Making this one more interesting is a current NPC companion (named Morakh) who was one of the Wizard's apprentices and is anti-elf. Also, there are signs of necromancy, with wights wandering the ruins so it's likely that one of the apprentices knew some necromancy.
Any other ideas?
