Very interesting how quickly you need to use the various mechanics to find a way that solves the puzzle for both sides! I also had issues with the smash ability, but thankfully I saw one of your comments further down explaining how to use it and I could try again. I didn't finish the game, but it definitely had a lot of potential.
The one thing I would suggest is to change the whole number/calculator thing: it would probably be easier to remember the abilities using different character sprites than having to associate the abilities to numbers (though maybe I missed something further into the game which makes the numbers important? I did reach the +1 mechanic, but that can be replaced with some other icon that basically does the same thing).