Such a cute presentation, I love puzzle games like this!
Difficulty spikes pretty hard after the 1st couple of puzzles (around the 1-5 and 1-6 range) 1-5 feels like a very important puzzle for the mechanics but the number of wyrms suddenly jumping up is a little intimidating.
Was slightly confused that you introduced a new mechanic in 2-1 but it doesn't show up again until a couple of levels after, but I thought the new block type was a really natural addition to the gameplay.
Played through with mostly using the mouse and for a slight improvement is there any way you could update the input so you can click and drag as well as click each block? Wanted to play through using arrow keys as well but seemed pretty unresponsive with just them from time to time, had to press a couple of times to register an input (every other input type was totally fine), not sure if there was something going on with my keyboard or there were some issues with input tracking.
Music track seemed to just play through once then stop for me as well.
Did play through all of the puzzles and definitely enjoyed my time (finished all of them minus 2-5 and 2-6), do have to say though, the smaller puzzles felt much more interesting than the big ones with a small number of wyrms. I'm sorry this sounds a little negative, but this was really fun and I'll definitely come back to play some more with any updates!