Someone on RPGnet was asking for oldschool rules that they could use for the PCs trying to climb in rank in a guild and some inter-faction intrigue. So I wrote this. It's quick and dirty, so it may need work. I've been thinking a lot about Sigil lately, so this can come in handy.
Each faction has a "philosophy"/outlook and one or more goals. Factions have relationships to one or more factions (rivalries, open warfare, tenous alliance...). The GM outlines those, along with faction names and important NPCs (or improvises them in play).
Upon joining a faction, a character gains the rank of Novice (1). Characters can gain "Faction XP" by:
-performing jobs for the faction, by receiving orders from superiors (fxp based on level of challenge)
-spending money on the faction (bribes, investments, donations; gp for fxp)
-eliminating or demoting higher-ups in a manner that's not noticeable, detestable, abominable or frowned upon in the faction (it might be acceptable to murder your superior and take their place in an evil assassin guild...doing the same within the ranks of the town guard...not so much)
Similar to class levels, faction ranks offer certain benefits.
Access - the member can request entry into buildings, meeting places, archives etc. of the faction
Assistance - the member can request protection, healing, training or similar assistance from the faction
Command - the member can give orders to those of lower ranks
Fund - the member can request money or similar resources of the faction and its members
Each request is considered a 2d6 reaction roll, based on the monster and retainer reaction rolls, modified by the character's charisma modifier (I'm assuming old school modifiers) and rank bonus.
2 - suspicion, hostility, rejection
6-8 uncertain, needs convincing, requires recompensation
9-11 agreement, acceptance
12 agreement and more
Use whatever xp chart you want based on how fast you expect the PC to rise in ranks. Here's a simple one:
Rank FXP required Rank ability
1.Novice...................0 fxp Access -1
2.Apprentice..............2000 fxp Access +0, Assistance -1
3.Journey(wo)man.......4000 fxp Access +1, Assistance +0, Command -1
4.Master....................8000 fxp Access +2, Assistance +1, Command +0, Fund -1
5.Grand Master............16.000 fxp Access +3, Assistance +2, Command +1, Fund +0
Alternatively, instead of a rank fxp chart, rank could be determined by relative amount of fxp. If there are only three guys in the faction and you have the most fxp out of them, you're the Grand Master. If you're the Grand Master with 18.000 fxp but someone gains 23.000 fpx, they push you out...but that would require more tweaking and calculations.