My opinion regarding doing walls at the right time vs doing them at a higher th level.. You will have to do the walls sooner or later, meaning you will need to leave your builders to rest for some time at some point. Why not do it now when loot is easier to find, than later when you will struggle more for the same results?
If you reach th9, I assure you the next time you will start doing walls will be when you max out your th9 base, and by then you will struggle a lot with weak walls in wars, maybe in PvP too.



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