1. If you can train BalloonsSame to Level 10, 11, 12. Like Canons, Mortars cannot attack aerial units.
2. If you cannot train BalloonsYou must train Giants, and you need 14 or more Giants. Inside of the walls, you can put troops on the pointed areas in the following picture.
In this stage, M is for Mortar, aerial defenses are not. Use a Ballon! Easy and reasonable!
If you don't have Balloons, use Giants instead. It costs you a lot.
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