Bring out your cults...

[Kyramus]

So you are looking for cults to fit a blasted wasteland?

The minions of Set.

The cult looks down upon the other cults, thinking itself to be of the strongest among them. They dabble into the other cults affairs, mostly making everything fail.

This cult could hire the PCs to interfere with several cults and the targetted cults won't think to look at the Minions of Set since the PCs where the ones that interfered not anyone from the Minions.

Then while the cults are busy, the Minions of Set go about thier plan of taking over the government and be the power over the city.

 

[Psychotic Jim]

How about some cult dedicated to some sort of Elder Elemental God of Death or something who manifests itself as all four elements. The cultists make sacrifices to the god/alien intelligence by killing people using the elements. There could be 4 subcults constantly vying for the favor of the god:

Fire: Sacrifices by burning people at the stake or smuthering them with smoke.

Water: Sacrifices by drowning or through water deprivation or Horrid Wilting spells

Air: Throw people into a wind-tunnel or something and batter them to death. Or just smother them.

Earth: Cave-ins are nice. Or pushing people off really high cliffs.

Perhaps there could be subcults within the subcults: one causing misery and death through an excess of each corresponding element, and one through the denial of each element.

 

[kkoie]

Cult of the Universal Dragon: a chaotic evil cult that worships a dragon that travels from world to world, consuming the planet. The belief is that the dragon is eating the worlds in preperation for armageddon, where it will spew out the contents of its stomach to create the next universe. Worshippers are encouraged to commit suicidal acts (thus the membership of the cult is always fluctuating) in order to impress the Dragon. The reason why the cult seems to survive so well, is its leader is extremely charismatic, and knows how to manipulate people. He hasn't commited suicide yet, because he feels his calling as a priest of the dragon is far too important. There are far too many other people who havn't slit their bellies to the dragon yet for him to cut his own.

Nameless Deathcult(name it after an evil diety of death in your campaign): This is a cult of assassins that actually worship death as an art. Each assassin has mastered a specific form or weapon of death and will use no other. The ultimate goal of the cult is that they believe that one day, one of the cultists will be chosen as an avatar of death, to lay waste to the world. In pursuit of this goal, they have a 'holiday' of sorts once per year, durring the fall soltice. One of their members is chosen (the technique for choosing the member is never the same, one year could be the best in a series of tests, the next could be a lottery) and is taking to the main sanctuary of the cult to meditate for 3 days. At the end of the 3 days, the chosen one exits the sanctuary and must fight and kill, every other member of the cult who is waiting to slay him. If the member successfully kills the rest of his cult, then the prophecy has been completed, and he must be the avatar of death, chosen to lay waste to the world. The greatest of the chosen cultists so far, is a member who successfully slew 7 members before being butchered by 3 others.

K Koie

 

[Bendris Noulg]

Okay, I'm working on using as many as possible; Most of these are easily adaptable, although you might have to strain your eyes to see the original suggestion within it. At any rate...

Cult of Isis (not the egyptian goddess, just used the name)

This one's a bit off from your suggestion, but fits the world-history: Druids of the Rain Keeper

I've got another idea closer to the original concept rollin' around in my head. I'll post a link if it takes full form.

I'll be back with more links as these develop...

Also, I do have a netbook, so if I use something of yours and you want the credit to read as something other than "Based on a suggestion by [Poster X] from ENWorld", please write me and it will be done.

 

[Jürgen Hubert]

The Cult of Shaprat, the Last City

Shaprat is an otherworldly entity/deity/sapient demiplane (the exact details aren't known) that seeks to absorb the world's cities into itself. Its cultists hold bizarre rites in cities, and if they are successful, houses, blocks, and even entire neighborhoods vanish from the Material Plane into Shaprat, and are likely never seen again...

 

[CCamfield]

This one is not entirely thought out yet, but...

The Servants of the Eater of Magic

The Eater of Magic is a powerful demonic godling that was crippled and banished from the world in ages past. Its worshippers were thought destroyed by most, but a few survived to found a secretive cult. The Eater was particularly feared because, as its name suggests, it sustained itself through the consumption of magical energy, and this made it incredibly difficult to defeat.

In order to bring the Eater back into the world, the cult must steal magical items, spell books, and the like to sacrifice - feed - to the Eater. This will naturally enough strip the items of their magic. As they sacrifice more items, the Eater will "approach" the world, and begin to have a draining effect on magic in the vicinity of the cults' shrines. If the Eater actually manages to manifest itself (through the sacrifice of a great many items or some powerful artifacts), an area around it is considered a negative magic zone, per the Geomancy section in Occult Lore.

For a very long time the Servants have been held in check in a sort of "shadow war", but they have now either gained a victory of those opponents, or their opponents are no more. In my game their opponents were the secret police of the regime of the city of Almara. Almara has just been conquered by foreigners, who have NO clue about the Servants, of course.

(Other details: I've been thinking about letting the Servants have a feat, Mark of the Eater or something like that, which dedicates a character to the service of the Eater, and makes them immune to the magic dampening and draining effects of the Eater of Magic.)

 

[Bendris Noulg]

Hey, folks... I haven't forgotten this one. However, we just did a revamp the The Reprieve site, so I've been distracted.

I'll be back on this in a few days, though...

 

[khyron1144]

Children of the Star of the Morning

A group of heretics and anarchists who believe that freedom and equality really are very good things. Some of them merely write incendiary poems, songs, plays, and essays that expose the abuses and/or silliness of current authority figures. Other members take a more direct approach to undermning authority and use violence and destruction to achieve their ends.
[This one is no very well fleshed out yet, as I just sortof thought of it on the spur of the moment]

 

[Lurks-no-More]

Pythagorus (the dude who theorized the Pythagorean theorem) had cult followers. I think it would be cool to have a cult based on the anti-thesis of geometry (if such theories are relevant in your campaign). For example, they believe that they can create a triangle such that all three angles don't add up to 180 degrees.

It's called non-euclidian geometry.

Draw a triangle on the surface of a sphere. It's angles are more than 180 degrees by default (you can actually get a rectangular triangle, ie. one w. 3 right angles...). And if you use concave surfaces, the angles won't sum up to 180 no matter what you do.

Now, if you do the rectangular triangle trick on a plane surface...

 

[Psion]

Well this may not appeal to you too much, as a cult I use in my game is more a rural cult and you are looking for a city, but IMC, there is a cult generally simply referred to as "the witches" that follow a demon queen named nocticula. The witches of Nocticula look for young girls with sorcerous potential among rural communities and make them part of their coven.

Incidentally, Nocticula is based on the same mythical figure that the "Nocticula" described in "Armies of the Abyss" is, but my version is more a patroness of magic and seduction. However, like Green Ronin's version, my version is capricious but can be relied on for help by bitter and abused women... but her help comes at a price.