Upgrade system is sort of like a recipe. When you buy a recipe you have to make the food (Or in this case buildings) BUT the food only disapears when it's eaten (Or in this case damaged). I think that it's good that you have to make the building once it's upgraded but you shouldn't have to make it more then once. If you get damaged enough then you should have to re-upgrade it but if you go through a level without taking much damage then you shouldn't have to re-upgrade the building. Therefore I don't like the upgrade system. If you like this idea copy+paste
has enybody else tried to make MY idea posablle i figured out the perfect graity for and upside down map ill tell u if u go on my profile and shout at me
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