Thank you for playing the game and for the feedback!
It was sort of intended (not entirely working), but if you spam the button you will run out of health faster and not survive as long as you could.
Staying close to a crystal also does not work that well, because the production speed is too slow to recover the health you lost.
I do want to change it into a different system where there are different areas, so that the player has to keep moving. I'll keep this in mind :)
Thanks again for playing!