It really is fascinating how this more or less set the expectation for NCs to all have the same structure and same gameplay and same deco and everything which held the vast majority of them back from being interesting, even though this is the reason they exist. You can even notice one of the other main reasons why most subsequent NCs suck already being in this level: the overfocus on the wave at the cost of all other parts. Add on the bad gameplay and this thing really set the standard low, eh?

Buen Nine Circles

Very cool level in concept, but unfortunately it has many flaws. The level has many bugs and the visuals aren't perfect. There is a part where it is seemingly random whether or not you hit a speed portal. The difficulty is also very inconsistent. I only finished it because I got so far and couldn't just give up. Play Jawbreaker instead, it's hard but it isn't a bad level.