Last Friday's 10x10 started a discussion and some people said they tried to do the Friday 10x10 without using pencil marks. So that gave me the idea of creating a puzzle that could be solved without needing pencil marks.

My challenge is to solve the puzzle below without using any pencil marks. Can you do it?

Using pencil marks would make it an easy puzzle, so if you prefer that then that is good too.

Thanks for the puzzle, really cool.

In the past I had the idea of doing a "1 chance only" puzzle: if you enter a number, it stays

No pencil marks, no moving back to a cell, no second chances

I suppose it'd have to be set up like a timed puzzle as well.

(otherwise just print, solve on paper, enter solution)

This looks like an interesting challenge.

I wont get to it right away, but maybe by the end of the weekend.

I just imagine that it will be very slow going,