Figure out what year the plague comes out, and move out all of your armies from your cities, or you will lose 1/2 to 2/3 of your full stacks. As Turks, I made the mistake of leaving my armies in my cities for retraining (I didn't know what year the plague hit), and after the plague was over and all my armies decimated, the Timurids thought it an opportune time for them to pop out