For this cheat, you'll need barracks (any level), army camp (any level) and laboratory (any level).First, choose a troop to upgrade in the laboratory.Let's say Wall Breakers for instance.As the timer gets close to running out on the upgrade, fill up your army camps with any type of troops.Then, fill up all your barracks with whatever troop is about to be finished upgrading (in this case: wall breakers).They will sit in the barracks and not be able to go to the army camp, due to campâ??s filled to capacity.Once the upgrade is completed in the laboratory, sell back the troops (wall breakers) that were sitting in the barracks.Youâ??ll get the upgraded elixir-cost, instead of the cost you originally paid for the wall breakers.