Tesla takes long time to upgrade. So some players don’t wanna upgrade it. However, tesla is the most effective defense for th9. High DPS and 2*2 space make it free to place anywhere.
2、 Wizard Tower
Wizard Tower is the best defense to kill ground farming troops. It’s often placed near storages.
Some players may hold different opinions towards it. With the longest range of any defense, X-Bow will dominate attacks. I would suggest to configured it to target ground units only.
4、 Air Defense
The importance of Air Defense is obvious. It’s the most powerful weapon to defend against air units.
Mortar deals heavy splash damage, it can quite rapidly eliminate attacking troops. It is better to place them in triangle or square.
Here is my th9 farming base.