In Epic Wars, such things a turtles doesn't stand a chance, therefore you never trust your defence to proctect your fleet or ressources. Still using defence, can be a very good idea, it will scare a lot of smaller players away from raiding your planet from ressources. There is a lot of theories about "the best defence", but there is a few things most people can agree about. Guasscannons, Ioncannons and Plasmacannons stands behind lots and lots of fodder and fire opon the enemy, recieving few shots due to the random shoting most likely will hit the fodder. A good defence could look like this: