I recall a line from a Terry Pratchett novel - the great general, Tacticus (a joke on Tacitus, presumably), is asked what is the correct course of action if you are outnumbered 3:1 by an enemy with superior armaments and logistics.
His advice is: do not get in that situation in the first place
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LA Mictlan is eating me alive with Imps and I'm not going to be in any position to stop him, so people should take as many of my provinces as they can. If I can win my main battles against him, maybe people can give them back, but that's unlikely
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