What's the point of completing the Hard and Insane Mission in the "CAMPAIGN," when you still have to purchase keys after you finished all the Hard and Insane. Why not let it be like the easy CAMPAIGN. Once you finish every hard and Insane using keys, then you can enter the Hard and Insane anytime. Make it like a real game. When you beat the master of that lvl, you gain entry anytime. It will make more people complete these task.