Here are my favourites, though this list may change soon-ish:
-All of the Nifflas levels (Isn't it obvious?)
-Absolute Machination, by Diago (Wonderful atmosphere)
-Cliffhanger, by Grimwit (Not sure why I love this one so much, but I do.)
-Dark Sea 2, by SecretGlitch (Oh Juni, this is hard, but very VERY well made!)
-Do Not Pick Up The Key, by Talps (My banner should have given that away
![:P :P](https://nifflas.lp1.nl/Smileys/Niffpack/tongue.gif)
)
-Harvest, by farik (Solid story and progression. All you could ask for, really.)
-Night 2, by Chezzy (I'm sure we've all been there, for one reason or another!)
-Scarlet Tears, by James Vaughan (The atmosphere for this one gets me every time)
-Station Sputzna, by farik (Even incomplete, this level is gorgeous to both the eyes and ears)
-The Extinct Bird, by Christian (The COs in this must've taken FOREVER!)
-The Hunt, by farik (Very interesting effects and settings, and decent humour as well)