Please help me write my campaign.

[frogglesmash]

The campaign setting is a Hellboy knock off i.e. small division of the FBI composed of supernatural beings who are tasked with handling supernatural threats.
The premise for the campaign is as follows:
A small group of teens accidentally summon a succubus (as part of larping session maybe). The succubus then kills most of the kids possibly leading one or two in a coma. The bodies are found and cops investigate, the succubus possesses one of the cops. The PCs catch wind of the situation and come in to investigate, and end up working with the cop who is (unbeknownst to them) possessed.

My problem is I don't really know what kind of shenanigans I should have the succubus perform.
The only idea I have atm is to make summon a number of lesser demons to help her wreak havoc.

Note: I chose a succubus because they are relatively low cr, and they especially good at infiltration.

[Crake]

What level and classes are the players? Because honestly, in a social game like this one sounds to be, succubi are woefully under CRed, especially keeping in mind that fiends capable of possession gain +2CR (assuming fiendish codex 1 rules, if using the fiend of possession class, then it's more like +6 CR because she also gets class levels), so what you're looking at is a CR9 encounter. If there is no spellcaster (which is what I presume, because it would make investigation trivial), then the players will be practically unable to kill the succubus, especially if she's capable of possession.

[frogglesmash]

What level and classes are the players? Because honestly, in a social game like this one sounds to be, succubi are woefully under CRed, especially keeping in mind that fiends capable of possession gain +2CR (assuming fiendish codex 1 rules, if using the fiend of possession class, then it's more like +6 CR because she also gets class levels), so what you're looking at is a CR9 encounter. If there is no spellcaster (which is what I presume, because it would make investigation trivial), then the players will be practically unable to kill the succubus, especially if she's capable of possession.

I'm aware that I'll have to tailor stuff mechanically to avoid a meat grinder situation, that's not what I want help with. What I'm looking for is help in coming up with the metaphorical bread crumbs that will eventually lead the PCs to discovering the succubus. In other words I need help coming up with"crimes" for the succubus to commit, and for the PCs to investigate.
As for the party comp, I don't know what it's going to look like yet, but I'm planning on starting them at level one, thought I would like to emphasize that game balance is not part I need help with.

[cullynthedwarf]

Instead of a Succubi had you considered their Devilish counterparts, the Eryines? the CR is only 1 point higher and a devil would have a plan to make others dance to her tune while the Demon would react to events around her. her chaotic and implusive nature wouldn't let her plan to far in advance. As far as Shenigans... her first game is going to see who is on the game board.

I call it the Rabbit hole. The Demon/Devil uses Abyssal/Infernal Alchemy to taint a supply of Narcotics so the effects are much worse. It is sending the vics mind into The Abyss/Baator while leaving just enough of it around to pilot the body. dozens of victims die screaming of Demons is what alerts the team to the tainted drug supply.

the Devil girl would have easy access to the warehouse of evidence that the police of the city would have on hand. you said that she was a possessing a cop. after a month of letting the tainted drugs on the street she stops because any one that is going to come looking has already made there move to find out about the supply. plus she can use theses jonesing addicts to build up a soul count for when the eventually OD on the product.

If your team has not discovered the taint by the end of the month the window will close as the tainted drugs are consumed and gotten off the streets.

The Devil girl can then begin a new game.

I keep calling this a game, because to the nearly immortal Devil girl it is, she knows that unless the team goes to Baator/ The Abyss they will never be able to permanently hurt her.

[frogglesmash]

~snip~

I kind of plan on using Demons and Devils somewhat interchangeably, and not sticking too rigidly to the lawful/chaotic aspects of their alignments. But other than that this is great, way better than what I was coming up with.

[cullynthedwarf]

The second game as my wife calls is it "Planting Sugar" once the pieces are on the board and they have identified them selves, its time to start tempting their families. Mom and pop are having fincial difficulties? she solves it. brother cant seem to keep a job, she finds him one he cant lose. Wifey is still in debt for student loans get them forgiven. and right when things look like they are going superb for every one BUT the PCs, TAKE IT AWAY. the bank had misfiled the paper work for some one else and mom and pops money troubles are back with interest. the job your brother couldn't lose burns to the ground a night he was there late and he is suspected of doing it, and the wifes student loans may be gone but her credit card has suddenly taken a nose dive and she has nearly the same amount of debt on the card that she had in student debt before, but of course at a much worse rate.

and as their dispair climbs higher and higher the Devil girl comes offering poisoned fruit. Just sign this contract and she will help things get back to how they were.

this time since the family of the PC are the targets you can give them a tangible clue as to who the devil girl is. some thing they can use to find her. a smell she couldn't erase from parents mind, a single defining feature that stand out to them, something like that.

of course if any of the family signs the contract stopping her becomes a much more personal quest. of course it also gives here leverage over them, "If you do this i might get rid of that nasty little contract mommy and daddy signed with me..."

of course this part will take time to build and to let the PC's here the rumors of it. so that takes to the third game. the blame game. The Cities Homeless begin to turn up dead with strange markings carved on their bodies. Using her ability to speak other languages besdies common and Infernal, she carves into them DEMONIC sigils that she uses to try to throw the PCS off her trail and on to a phantom Demon that isn't there. it will probably take them several games to figure out that she has just been jerking their chain about this and by that time they should have heard about the good fortunes from their families