I absolutely love this game! The charming 2D pixel artwork is fantastic, and the puzzle mechanics are enjoyable. It strikes a nice balance of challenge, especially with the gradual introduction of new mechanics through the levels. Even if you didn't read the tutorial, the introductory levels effectively convey the ideas and mechanics, gradually ramping up the difficulty and testing your knowledge of each mechanic. It's a great approach that I really appreciate!
I must also commend you for the seamless integration of the theme. It fits perfectly and adds to the overall experience. If I had to nitpick, and I mean this is a very minor point, it would be the music. Personally, I feel like it doesn't perfectly align with the game's atmosphere. However, I understand that music preferences are subjective, and the retro chiptune sound does have its charm. It's just that it doesn't quite evoke the feeling of being in a cave trying to rescue my cave pal imo. :/
That being said, I want to emphasize that I'm being extremely picky here because overall, I adore this game! It has easily become one of my favorites. The combination of delightful pixel art, engaging puzzle mechanics, and a well-executed theme make it a standout experience! def playing this more in my spare time haha!