Crane - > Sensates
Crab - > Bleak Cabal
Dragon - > Transcendental Order
Phoenix - > Fraternity of Order
Mantis - > Fated
Scorpion-> Mercykillers
Lion-> Harmonium
Unicorn->Doomguard
Kolat->Athar
Imperials-> Sign of One
Brotherhood of Shinsei->Godsmen
Shadowlands/Spider->Xaositects
Lying Darkness/Nothing->Dustmen
Ronin->Free League
Your thoughts on this?
This is good start, but I think that some of them should be changed.
You see clans and factions are two diferent things. Clans of Rokugan are union of families that share common divine ancestor that founded them and their role in empire where set by emperor Hantei. (but you allredy know that if you play L5R).
Factions are on other hand are political organisations bound by simmilar belives and aligment, their roles in Sigil were given to factions that were fit to preform such duties by Lady of Pain.
So here I will give my ideas what mayority of wich clan would belong to wich faction.
Crane - > Fraterenity of Order (Becaouse Crane are politicians of empire), Sign of one and Fated (the most snobish of the Crane)
Crab - > Harmonium, Mercykillers, Fraterenity of Order, Fated (They keep back the chaos that is treath to empire), Bleak Cabal (only oldest individuals), Ragers (Crab Berserkers), They could be Doomguard only in terms of keeping doom at bay and not embracing it.
Dragon - > Transcendental Order, Sign of one (that is selfexplanitory becaouse it has points with zen phlosophy that the world is illusion)
Phoenix (yuck, I hate them) :x - > Fraternity of Order and Incantifers (laws of nature and masters of magic)
Mantis - > Fated and Merkhants-sect, Indeps, Sensates (they are focused on the profit after all, and in disposition are similar to unicorn who mantain contatcs with forigners)
Scorpion-> Mercykillers (I have no better idea for those but I guess that even some AntiAnarhists could fit into Scorpion, after all their divine duty is to keep clans at each other throats)
Lion (my faworites )-> Harmonium and Fated (they keep peace in empire and one of them had become new emperor).
Unicorn-> Sensates and Planewalkers guild (becaouse Unicorns are of all clans open to new ideas and have contact with other cultures)
Kolat->Athar, Godsmen, Transcendent order and Free League, Anarhists (they want free empire from gods and old imperial families and that empire is ruled by ordinary man)
Imperials-> Fated (becaouse they role in empire where given by fate and gods themselfs)
Brotherhood of Shinsei->Godsmen, Sign of One, Transcended Order (same with Dragon)
Shadowlands (my second faworites )/Spider->Xaositects; Doomguard, and Anarhists, Bleak Cabal, Dustmen, Fiends (They represent forces of chaos and disorder and undeath that threathen the empire)
Lying Darkness/Nothing->Dustmen and Turncoats
Ronin->Free League (mostly but any faction could fit with these)
So there is it: after all Rokugan is extremly Lawfull (and that means Good in eastern cultures) so most clans can be asociatd with some Lawful faction while outsiders and Shadowlands represent forces of chaos (and that means Evil in eastern cultures) so I gave Chaotic factions to such outsiders.
Neutral Factions members could belong to any clan but only in minority of number.
That is my opinion anyway.
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