Finally, good levels! Never thought I'd see those pop by. The levels look pretty nice and you have a good attention to detail when it comes to decoration and props. These stages were hard, but the difficulty was well balanced so you eventually want to keep trying until you finally beat it.
Thanks, I tried to keep the levels at a moderate difficulty. Not impossible, but will take many tries to complete.
And yes, it is disappointing to see the portal being spammed with 50x40 forest tile levels with hazards scaled using the shift key.
Pillars: This was a really clever gimmick you had going there. It's well executed, too. The level itself was pretty easy and simple, but this section was worth the admission.
Pillars was an experiment with way-points and hazards that I really didn't want to copy onto a new level. It took me a long time to get the stream to cut off/flow realistically in sync with the platforms.
Keyline: You can still jump to the other side of the final pit even though the bridge is gone (by doing a walljump). Was that intended? If you wanted the player to obligatorily use the bridge, you might want to place hazards that'll prevent the player from walljumping.
Keyline is supposed to be a speed-run level, you should try to beat it as fast as you can and having a key-bridge is good for that. Being able to wall-jump it without the bridge was intentional, I didn't want it to be impossible to finish the level if you weren't fast enough to get to the bridge before it went out.
Airborne: It was sometimes tricky to orient yourself properly for the jump due to the absence of "rain" graphics highlighting where the wind of the fans blow. Then again, littering the whole playfield with those probably would also clutter the whole level and make it unappealing... so take this suggestion with a grain of salt (pun intended, obviously)
I did try putting the wind/rain effect by the fans, It was hardly visible and didn't look very good so I got rid of them. I might add them to the fans that are more powerful than others. The ones that have a stronger push are in front of the sawblades, I tried to make it easier to be flung over/into the sawblades.
@Ckarasu: HX1 was made based on dodging saw-blades quickly. I did attempt to make it as short as possible without removing the challenge.
I might also re-make each level for a dark-world chapter.