Yea the game is beatable. It's just lacking of instructions. Tips: A lot of people missed how freezing the town becomes more effective as you have more power. Don't even bother holding "e" between levels unless you're over 70 power or so, or else you'd be wasting it. I figured this out at about wave 15 (until which point I was barely recovering lost health) and completed the game at wave 27. I didn't bother with the ultimate and the double jump, as they both consumed power.