I really would like to have some constructive criticism on my game "Chessman".

https://kimhollesen.itch.io/chessman

If I were to criticize the game myself. I would say the following :

The basic idea of the game is very interesting,  and the best thing about the game.

The level design could perhaps be better in some cases. 

The difficulty curve is not perfectly linear. There is a difficulty curve, but it is not a consistent one.

Maybe some levels are too hard. On the other hand. There are some levels in the game,

 that I find enjoyable.

I do not know what makes a level enjoyable. This may vary from person to person. 

The rules of the game should perhaps be explained inside the game, as tutorial levels, 

instead of as a seperate help section.
.