You need to know the strengths and weaknesses of your characters in order to employ tactics that will win you many battles. It will be easy for you to know how and when to use certain characters when you know their strong and weak sides.
Make use of the terrain to kill more enemies. For example, you can first eliminate enemies that are in forest squares, small gaps or choke points as they are pretty helpless in these zones. You can also use the Danger Area button to know places that your opponents can or can’t occupy.
Another battle tactic is to avoid being surrounded by your enemies. You need to position your troops accordingly to avoid being surrounded by your opponents or use natural barriers to thwart any attacks from opponents that come near your bases. Other tactics that you can employ to win many battles include doing nothing at all at some times and causing your enemies to react first in order to act accordingly.