Some adventures are nice simple locations where bad things live and wait for player characters to come and slay them. Others are railroaded plot-heavy stories that are a game in name only. Some are mainly locations full of badness that only make sense if you understand what's going on behind the scenes and ToEE is one of these - otherwise it might be a little confusing as to why, after fighting through level after level of Air, Earth, Fire, and Water cultists, you end up fighting a giant fungus monster. Backstory - sometimes it's important!
So why are all of these elemental cultists gathering together? What is their goal? Who is their leader? Why is there infighting that the PC's can take advantage of in the lower levels of the Temple? Why did so many people in the old days think that guy in the Moathouse was a follower of Lolth? Is there a way to have all of these things make sense AND communicate it to the players? Let's dig in.
The original plot involves Iuz and Zuggtmoy (two lesser divine powers) getting together to fool people with a new cult and gain worshippers they might not otherwise get - it's like a marketing plan to diversify their product line. Iuz is traditionally opposed by St. Cuthbert (who makes a guest appearance at the end of the adventure if Iuz steps in due to some bad player decisions). Lolth comes around after the initial fall of the temple and starts trying to restore it and subvert it to her own purposes - everyone wants to set up shop on the surface world, apparently. I could just follow this background and substiture some divinities: Torm would replace St. Cuthbert, Moander replaces Zugtmoy, Lolth is still Lolth, and maybe Bane replaces Iuz. This is the simplest approach, but I'm wondering if I'm going to move it to a canon-filled world if there is not some way to take more advantage of some of that material.
The Realms used to have a god for each of the four major elements of Air, Earth, Fire, and Water. Now for 4th Edition they have been reclassified as Primordials but they stil exist. There are also the Princes of Elemental Evil originally from the old Fiend Folio - Imix, Ogremoch and the like. I'd really like to tie these elemental gods of the realms to the elemental cult somehow. Maybe those moonlike objects in the elemental nodes are the incubation chambers for the elemental princes of evil, and destroying the links means that they open and the new princes awaken in the Elemental Chaos - that could stir things up, and ties them into the party for a possible showdown at Epic levels (they're level 30-something solo nightmares in the 4E Monster Manual 3). PC's might be followers of the elemental gods sent to find out what's going on with this temple dedicated to the four elements but not to them.
In the G and D series adventures the Drow make their first appearance and there is a rivalry present bewteen two things worshipped by the Drow - Lolth, and the Elder Elemental God (also known in the Realms as Ghaunadaur). Since I'm looking to run those adventures after the Temple I would like to bring in those two gods now as well. They were demon lords in the original modules, but by the time of the 4th edition Realms book they are both Greater Gods. Lolth ascended by slaying most of the other Drow gods and running Ghaunadaur off into the divine wilderness. Ghaunadaur became the god of slimy lower life forms and over time regained enough power to ascend to Greater status. Perhaps he has decided it's time for a rematch?
We also have Moander as a replcement for Zuggtmoy, star of the original adventure and the utltimate adversary for the party.
So, sticking to the core idea, a particularly bright priest of the sort-of-dead god Moander hatches a scheme to gain a lot of followers and enough power to free and restore his dead god. He decides that Elemental Evil has more appeal to a broad range of miscreants than the orignal rotting and sliminess of Moander and so starts the TOEE. The followers of the various elements have never gotten along well which would make this deception relatively easy as they are too busy watching each other to pay attention to the ultimate leadership and figure out that the story is a complete hoax cooked up to pull in followers and resources. Things went well for a while but eventually the scheme backfires (years ago) and ends up with the last avatar of Moander imprisoned in the basement of the smashed temple.
I am aware that this is a pretty sophisticated scheme for followers of a fungus god so clearly Lolth was there from the beginning.
From the wiki:
If any deity in the realms can truly be called 'dead', it is Moander. However, there is still a tiny fraction of his power that still resides with his corpse which now floats through the Astral plane so theoretically, he could be revived, given enough worship.
So this is how Lolth comes in - she's looking for a way to take a war to the surface elves and the corrupting power of Moander is it. Thus she is aiding the cult to bring Moander back but under her control. She is also thinking that it would be good to have another slime god in her camp to oppose the power of the EEG. Additionally, since the EEG has started making inroads on the surface world with his giants, she intends to have her own organization on the surface to work against him there as well.
So, the followers of Moander, aided once again by Lolth, have recovered enough to try again and are busy restoring the Temple and drawing in new followers. At some point a partnership with Bane comes into play too, so we're back to a trilogy of deities behind the scenes.
The deity involvemnt is important to nail down because one of the conceits of the original was that Zuggtmoy was imprisoned in the temple and the various magical seals on the doors (that the PCs break as they descend) are keeping her there. The climax of the adventure then involves an avatar of Zuggtmoy getting loose and the PC's having to take her down, and I think an avatar of Moander will work just fine in her stead (fungus deities have to look out for one another after all). There is a similar story in the Dalelands where Moander is supposed to be imprisoned underground in a remote part of the forest so it ties together fairly well with previous Realmslore. Let's call it a nod to canon, but I'm more concerned with getting the Temple right than I am getting the Realms history right.
Moander's curent state - Evil deities never die, they just wait for the next edition!
For leadership there is a leader of each elemental cult, various guard captains, a high priest over all, and several agents of Lolth behind the scenes keeping things quietly efficient.
Now I at least feel like I know what's going on with the temple. Good, but how do I let the players discover enough of this to get a picture of what they are truly dealing with? One layer at a time.
First, the local rumors are about bandit raids and the general suspicion is that they are coming from the old moathouse and the PC's will be directed there. Within the moathouse they will discover evidence that the Cult of Elemental Evil is active again.
Second, returning to the village they can pick up some history in Hommlet about the temple and the forces involved. This will all be about the elemental aspect of the cult as that's all any of these people really know. Air-Earth-Fire-Water, evil priests, demons, devils, elementals, evil elemental creatures, and plain old humanoids were all known to be a part of their forces. The goal of restoring old powers to life is slightly less well known, but can be discovered by asking the right people, mainly those who fought in the battles back when the temple rose up the first time. Armed with this information the party can proceed to Nulb and the ruins of the temple.
Nulb is the first place where evidence of Lolth might be discovered as she will have an agent in the village to keep an eye on things and the agent will have some kind of symbol indicating their true affiliation. There may also be an easily discovered Moander cultist as well, probably presented as a warped druid. This is just foreshadowing, as there will be nothing to link either of them directly to the temple - perhaps its nothing more than evil cults keeping an eye on each other although the presence of a Lolth-follower above ground is unusual.
As the players invade the undertemple and fight through the various levels, they will run across clues and hints that the elementalists are not the only religion being practiced down there. Bane's influence will be obvious beyond a certain point. Lolth's involvement will be sketchy but clear to those who know what to look for, while the Moander plan will only become clear near the end, probably on the final level of the temple and the last part of the campaign, perhaps through a supervillain-esque monologue by the true high priest, revealing himself at last and giving the players a brief warning about what they are about to fight. Since they are probably geared up to fight elemental creatures, it seems fair to give them a chance to discover that their big enemy is not really tied to an element. If not, oh well - 4E characters are pretty tough, right?
Now the best part about all of this is that it helps me understand things, but the players don't have to care at all! It's there for them to discover and dive into the lore if they wish, but it doesn't have to be found or acted upon to let the adventure continue. The bad guys do have an agenda but there's no plot-hammering timeline tied to it. In fact, the players can merrily smash their way through the whole thing if they wish to do so or they can go for some stealth and intrigue by playing the factions against each other and making and breaking alliances as they go - it's up to them!