I am level 845 now. From what I've experienced, in order to complete mission, you MUST spend money and buy boost or else you won't complete anything. This game isn't random. It give big wins based on your winning records. I have almost 100B coins, and gone just like that in one slot (bet 150M & 300M). Missions are ridiculous, win 15B coins in free game bet minimum 150M?? Dude, I've spend my hard earned 100B in 1 slot only get 5 free games, can't even reach 5B wins. I'm uninstalling.