I think it would be a really cool feature to add some kind of survival mode to the game, you pick a layout just like with friendly challenges, and then your base is tested against waves of troops, and various attack strategies, and possibly add in a system of resources, like for every wave you survive you get gold and elixir, you can use gold to repair walls and defenses, and you can use elixir to buy defending troops for your clan castle, or something like that, and every x number of waves you survive you get loot for your actual base, and you get a place on a leader board for your townhall level, i just think a system like this would be very nice for testing layouts and it would give players something new to do.
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