So, did another playthrough and I liked it. Worked fluently without any problems. Nice game! Just a few things I noticed, which are minor:
- I'd suggest to use Z for jumping and X for 'action'
- The rockets feel weird from a story-perspective. Why would there be single-use one-way fueled rockets in a cave system? Bit of a lame remark, I know, but just a thought.
- Another lame remark, at the end of the game you suddenly lost all your powers, made me think it was a dream or something. Would be more 'consistent' if the powers were still there.