Not bad, unfortunately the obligatory indie game bad balance is awful here. I breezed through the first 20 levels only to have lvl 21 be impossible, so was forced to reduce the difficult and then couldn't get killed if I wanted to. Then, the poor platforming killed me several times after that, so one small error forced me to re-do the entire 10 floors again. That really sucks, I hate when small stuff like that kills the enjoyment of a game.