Pretty decent hack. Though, a couple of custom bosses are pretty janky and rough, on top with them being placed somewhat deep into levels. The kaizo section in the castle is never gonna be done without savestates, but that's optional thankfully.
Other than those issues, this was a pretty fun short hack
Level design is usually quite good. They are sometimes long, but fun. They're also quite hard but they're never unfair, which is quite nice. There are some quite nice and unique gimmicks, too. Though, there is an issue: midway points. I think this hack should've had way more midway points. Another issue would be item babysitting. It's not so fun because it makes spinjumping harder. You have to be careful to not lose it, too. Other than that, it's quite good.
Everything else it's outstanding. Even though it's a hack from 2010, I think it's still good for 2015 standards. The palettes are quite nice and the music is nice and fitting - but it's broken in accurate emulators, sadly. The story is quite nice too - it's well-thought and very unique. The sprite replacements are really nice additions - nice idea there.
I remember playing this years ago and thinking it was awesome. It still feels as awesome as it used to. Nice work.