81/100 stars!
I had to edit my review which was initially 5 stars and it all boils down to a stupid issue that would be pretty easy to change. The technique tutorials that begin each section use the weirdest cell numbering convention. An example to illustrate: If we assume that cell (2, 2) doesn't contain the number 2 than it follows that cell (8, 7) must. The problem is that the cells highlighted in the puzzle are not located at row 2, column 2; row 8, column 7; row 7 column 8; or any other cell one might logically say is designated by those coordinates. I don't know if I'm being completely dense or if there's some glitch but please fix this. I am specifically referencing the turbo fish tutorial in chapter 14. Original review: So good. I'd pay money for a version with his support. I just sent feedback to the developer via the in-game feedback form. I really hope I get a quick response!