I enjoyed a lot the gameplay. I kept playing it until I actually completed the game. Well done.
The art is very cool. Just the hitbox of the last level is a bit weird but if you keep near the golem it's still playable. Overall a great interpretation of the theme, please add more levels :)
Those are some things that I would change:
1. I would add a tutorial that shows the keys to use so that you don't have to read the instructions (I did at the end)
2. I would make the jump a bit higher so that when jumping you surely don't get any damage
3. Add a cooldown to the Z key
4. Of course, as I mentioned earlier, add more levels so that you keep the user playing (It's pretty nice when you understand the gameplay and you get deep into it)
This could be a very nice game if you decide to continue it. Great job!