- Every provinces or countries of the map/game have a climate and weather. It is either balance, hot, cold etc. Units when conquering provinces will face this kinds of situation.
This changes will affect the provinces,(maybe doctrine) and the daily upkeep. The longer the units stays on that situation, the more suffer and higher upkeep will cost.
For weather changes, add also sunny, rainy, storm days etc. Maybe this can change the game like climate does.