Luna is sent, along with young Twilight, to old Neighpon to try and quell the feuding warlords with diplomacy. And, if that fails, reduce the bloodshed as much as possible. Turns out that Luna is the kind of mare that likes to jokingly flirt and see how far she can go to make the other uncomfortable.
Boy is she in for a surprise.
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So the inspiration for a lot of aesthetic and naming is primarily Japanese, however I'm taking from all of the orient and I'm being fairly loose with the accuracy. Translations and terminology won't be exact, don't expect a historical rendition of feudal japan in pony form here fellas.
Will update tags if more of them become relevant.