I also think it would be really useful to have an in-game troop/commander/province count for your nation. Probably in the Nation Overview screen. It would be much less mind-breaking than trying to count them all by hand and calculator on the occasion you might wish to
I don't know about anyone else but there are times I find myself wishing I was playing sp games on the llamaserver to have more access to that sort of data.
Also, about Yomi- Being used to the idea of demons being associated with human sacrifices etc, it feels very weird that Yomi, the only actual nation of demons in the game, doesn't have any blood magic or demonic summons iirc. I suppose it's probably not as thematic with japanese mythology as it is with others, I admit I have a pretty poor knowledge of japanese mythology.
One thing that would be really nice is if the kuro-oni could be made sacred. They seem like they're supposed to be somewhat more 'special' than the other recruitable demons, and what would be a good bless for them is certainly not one of the more standard bless strategies. They would probably have to cost a little more, but I really think they would make for fun sacreds. Plus iirc the Jomonese nations never have a very good chassis for a bless strategy, so it would add more diversity to them
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