Hmmm,
Frankly, if I were to do a WHFB Chaos game, i'd create factions by ethnicity rather than patron Power.
So, instead of the Khornate, Slaaneshi, Nurgling and Tzeenchian nations, i'd choose Norse, Kurgan, Beastman and Hung (I'm sure there are more).
But that idea starts to break down due to the fact that you can't mod your nation's mages to only have Paths and National Spells based off your Pretender
Ah well...
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