As others have said, the jumping is much too fast, especially considering the low spikes scattered about. The level-getting-easier idea is interesting, but it's simplistic (I died on an enemy robot, so it takes away lava but not that robot), the level reloading takes a lot of time, and there's no quick way to restart if you're going for score. With the reloads and lack of shortcuts to cancel score tally / jump to next level, the actual gameplay time is a fraction of the time spent on loading or menu screens.