One of my favourite implementations of the theme and limitation so far. Very tongue-in-cheek, but also makes for some very interesting mechanics. I love the little character designs, and I find the colour palette to be very pleasing. The audio is execute competently, the music is enjoyable, but doesn't draw too much attention to itself when you're stuck right into puzzle solving.
The mechanics are used very well to create interesting puzzles, but even the first level feels like it should be a mid game sort of difficulty. I think the game would really benefit by introducing each character and mechanic one at a time, rather than throwing it all in in one go. You'd probably double the length of the game, people would be more used to the mechanics for when it's time to get stuck in, and it would make for a more satisfying pacing.
Incredible effort, especially for a solo dev. Puzzle platformers are not easy to pull off, let alone in such a short time frame!