D&D 5E A Banquet In The Nine Hells

[MortalPlague]

So far, I have a pretty good list of NPC devils. I'm going to tweak some of them, and I'm probably only going to use Titivilus straight from the book, rather than the whole court. Any of the ones I change, I plan to rename so as to avoid confusion if any of my players know the court.

I may have Mephistopholes make an appearance. That name is simply too much fun to say.

As for the other NPCs, I'm planning to have a few subtle factions. Primarily, there will be two rival archdevils and their supporters forming two factions. Dispater and Titivilus are a third faction, largely neutral in that dispute. Then there will be a fourth faction of other devils who aren't involved, but could be drawn into things.

I have an assassin PC. I think he'll like the opportunity to work with one archdevil to covertly slay another, so that proposition will be put forth. Of course, there will be areas it can be discreetly accomplished. Or areas where it will incur the wrath of the court. I know the musicians will intrigue another of the PCs (an elven bard). And the whole thing ought to be suitably strange and wonderful, with a menacing undertone that the players have fun.

On the topic of demons, I don't think I will have them there. The diplomacy angle isn't one I'd want to explore. And the invasion would be better if this were a bigger part of the campaign. If the players are looking for combat, the assassination could serve, and the fight with a pit fiend would give them another opportunity.

 

[Beleriphon]

MortalPlague I don't know if you need this specifically still but I recalled an awesome scene is Cold Days (the 14th Dresden Files book) where the titular character is invited (shanghied?) into attending a birthday party (for him) held by Mab the Queen of Air and Darkness and must contend with factions that don't like him as well as factions that don't like each other. At point he's challenged to a fight and needs to nagivate his way around since he could just kill the one affronting him, but it would me a death sentence for him since no fight allowed (also no talking to the Mab unless spoken to first for the same reason). At its heart the whole thing to get Harry to fight so he'll be executed for breach of etiquette.

I guess my whole point is that Dispater should have stupidly arcane rules of etiquette and behaviour, that everybody but the PCs fully understand and comprehend. They are super literal though, so long as the letter of the law is followed followed the spirit is irrelevent. In fact I'd have Dispater take a spirit of the law view and if the PCs can be literal enough I'd let them have their interpretation.