Come to think of it, there's a tendency to think of "Free Sartar" as a monolithic bloc when we know now that multiple pro-independence factions took awhile to gel into a coherent rebellion.
If you're not eager to open up an Esrolian front (which I kind of like given how the Red Earth Alliance distracted Tatius, but it would be extremely complicated), how about spliting "Sartar" into some combination of Kheldon, Heortland, Colymar and miscellaneous "Argrath" forces to start? They'd be small but defensive.
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