The game is great, really enjoying the mechanic but TBH I think you are doing yourself a disservice with lack of initial tutorial/instruction. Once you understand what the mechanic is, progression becomes unobstructed (I wanted to say trivial but there are some tricky levels). Unfortunately you might loose some players right off the bat with that first level and that initial mystery doesn't do anything for the overall gameplay.
Really enjoying it tho!
Edit: After about an hour or so this is how far I got through your game. Some of the levels were bloody tricky.
https://imgur.com/gallery/2SYT0zY
The game is great, really enjoying the mechanic but TBH I think you are doing yourself a disservice with lack of initial tutorial/instruction. Once you understand what the mechanic is, progression becomes unobstructed (I wanted to say trivial but there are some tricky levels). Unfortunately you might loose some players right off the bat with that first level and that initial mystery doesn't do anything for the overall gameplay.
Really enjoying it tho! Edit: After about an hour or so this is how far I got through your game. Some of the levels were bloody tricky. https://imgur.com/gallery/2SYT0zY