@antti-haavikko Thanks for the feedback!
The singing comes when you hit a multi-colored portal which gives you the ability to destroy all the treasure. It is supposed to be a goofy power-up song similar to when you get a star in Mario. However, after exporting the game, I noticed that it loops forever once you get it (and I didn't want to cheat and change the game after the fact).
I agree that the portals could use some work. I wanted to keep a platforming element that made players either actively try and avoid portals they didn't want to hit or actively seek out portal by any means necessary. I didn't have much time to balance it very well so it stayed random.
I had a hard time dealing with the explosion. I was going to add a longer timeout but realized that it was almost essential to be able to use it often in order to break down blocks. I found that the more you broke the blocks down, the hard it was to hit them and make them disappear (which was enough of a "penalty" for me given I was running out of time). I like your idea of it destroying the smallest blocks though (I'd have to add a warning to the blocks, however, to let the player know that once they explode near them, they'll be gone forever).
The art and sound took much more work than expected. I thought by drawing everything it would save me time, but I was way off. Thanks for playing!