The game looks good at first but then you realize that this is a pay-to-win game. Your progress starts slowing down because everything is more expensive to pay and they give you too little credit rewards. If you don't have credits to upgrade your weapons, your robots and buy better ones, you can't win. To win, you need to spend your real money. An annoying issue is their server, i kept getting "Internet connection error" while the network was still fine.