Thank you so much for playing!!
I should add that the 'solve the previous puzzle punishment' only happens on certain levels where it's very important that the player understands the newest mechanic (i.e. the health potion on level 0-3). So it's not meant as a punishment, but as a helper to make sure the player understands. Otherwise the rest of the game could be confusing. Most of the levels do not send you back.
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Thanks! Maybe it felt excessive only in my playthrough, because I think I understood a puzzle, solved it successfully, then failed the next one and had to repeat the process I already did with the previous, where there were no problems. Sorry that I was wrong about amount of levels with that mechanic, I guess I failed only 'important' ones :)