Three brutally difficult Knytt Stories challenge levels by the author SecretGlitch. Although savage, the challenges are generally fair and typically no larger than a single screen. To my knowledge, this is the first recorded completion of this trilogy.

This is only the successful clips of each challenge taken from my playthrough of these levels. You can see how long it took to progress past each one by the timer in the bottom. The full playthroughs are available on twitch:
[Safety 1 and 2] https://www.twitch.tv/videos/75251238...
[Safety 3] https://www.twitch.tv/videos/87271974...

Music used:
Saturn (Lyle in Cube Sector)
Battle Royal Dome (Pokemon Sun & Moon)
Crocodile Cacophony (Donkey Kong Country 2)