How to find the amount of XP in an upgrade or build
It's simple really...take the square root of the number of seconds that the upgrade takes to complete. (read that carefully) For example, a lvl 10 cannon takes 4 days to upgrade. Take 4 x 24 x 60 x 60, which equals 345,600. Next, take the square root of 345,600...which is about 588, the amount of xp you will get for a 4 day upgrade. A 5 day upgrade will give you 657 xp, while a 10 day upgrade will get you 930 xp. Hope this trick helps all of you guys wondering how much xp you will get for upgrading or building a tower or structure. We will have to see if in the future we can get xp for upgrading troops.