I mostly create WoG levels, so here are some of the best!
Difficulty Level: Hard - OCD: Complete in under 1 minute and 40 seconds
Gear Grinder is my first published WoG level. Gear Grinder is a difficult level where you need to build upwards and to the right to get a Sticky Bomb, then blow up a destroyable block, and finally build upwards to reach the pipe. The difficulty comes from two gears which grind clockwise and counter clockwise respectively from left to right, which will pull down most or all of your gooballs if even one attached one enters it. The OCD is also quite hard, being suprisingly short. A perfect run is likely needed to pull it off.
Download it here: https://drive.google.com/file/d/1tXb__Zx8BLMh-XfoNJpobpT70EgAyLkD/view?usp=drive_link