Wow, thanks a whole bunch for all the awesome feedback! A lot of effort was put into trying to make all the levels feel really different so im glad you noticed! And its great to get to know how some of them could be improved, because i agree, not all of them are winners. Also a undo button was planned but i quickly realized it would be too compicated to implement on the limited time scale, with keys and doors and dead slimes also having to rewind, but definitely something to add in the future!
Again thanks a bunch for all the detailed feedback!