It's a cool idea, he's made tons of progress on different game mechanics and things. Certainly needs some balance tweaks and polish done to a lot of it (the physics look very strange and appear buggy sometimes), but I'm guessing it's because this is still early in development. Certainly will keep an eye on this one!
Having played the 5.0 alpha, I can definitely attest to the physics being strange at times. Maybe it's due to this laptop not being the best it could've been with gaming, and if it is, then feel free to disregard, but Chapter 3: End of Chaos for me right now is unbeatable without a set of movement speed boots on, as there are a couple jumps that I just can't seem to make the way that would normally be feasible in the actual game. Which is going to be problematic considering the route needed to even stand a chance at getting to the boss.
Although it was also pretty funny to watch that hammer whack all of the boss's weak points in one swing if he positions himself poorly and jumps. Managed to beat Normal mode in that manner by complete accident. Dunno if that's something that can be managed in the actual game, but if it isn't, there is that.