Eydi released Pico's Puzzle UFO: Shooting Stars for Pico Day 2023 and it's a damn hard but good (once you get the hang of it) puzzle game that has left a lot of people stumped. A u-toob walkthrough of the regular levels has been posted, which doesn't include hidden bonus levels. After you get the gun, you can backtrack to the first level and take alternate paths to get to the bonus levels if you're up for it. And they require you to make use of a funky mechanic -- if you press R to reset a level, it doesn't reset everything on the level, just the island that you're standing on at the time. You have to make use of that mechanic for these levels.
Even getting to the bonus levels is tricky. Now that you know they exist, go try finding them and beating them, but if you get stuck then here's how I did it. (Images are here on NG, not a youtube. Green arrows are movement, red shooting / resetting.)
Getting to bonus level 4 (yeah I did 4 next)
TharosTheDragon
The YouTube walkthrough also left out the Easter egg in 10-4