Not very fun I must say. This hack basically coinsists in plain ground with enemy spam on it. It's a repetitive design, which also has some small issues like blind jumps and unfair deaths. The levels also feel short, since, again, most of them coinsist in flat land. The brightest example is the last castle: generally, these are those levels with the tension to max, but this one here does nothing but spamming the whole lenght with thwomps. It's disappointing.
Aesthetic-wise, it's acceptable. Except for that ugly forest GFX the author used, everything looks okay. Maybe I would've decorated some levels more, but it's just a small niptick. Some palettes also felt a bit weird, like the black goombas.
As only issue worth of mention, music breaks on accurate emulators.