Is there a good free site where you can add colour to cells for things like x wing/ swordfish etc?

I play on this site sometimes

https://sudoku.com/expert/

but almost all the expert puzzles are solvable without any advanced techniques.

I have seen sites with tougher games, but having some colour options for cells (as well as number notes) would be nice.

Try
https://sudoku9x9.com

What I really like is the option of using both corner and center pencil marks to differentiate between 3x3 grid logic vs specific cell logic, but I haven't found that anywhere.

f-puzzles.com is the place people design puzzles in the CTC server.

I find Simon to be much more inquisitive and also explanatory. Mark kind of just rips through things some times.

Yeh, Mark's a puzzle beast and is used to doing everything super fast, which is why he wins everything.

thx everyone for the suggestions

I have done about 10 on this site. The ones at graduate level are good.

But, I have only encountered one where I had to use any advanced techniques.
(i.e. X wing, XY wing, or Swordfish)

It was puzzle #559982054 it stopped me dead for a bit.



A couple of thoughts on the site.

1. I wish it would auto clear same number notes in a zone (and associated row and column) when you have entered a number.

2. The solver is neat. I ran it after each game, and in each one it referenced one or more X wings or XY wings at some point, but I didn't have to use them to solve the game?? That seemed odd.

I am assuming that lots of eliminations we make by looking at the board can also be logically solved in a different way by a program, and either method can lead you to the same result.

I do like the puzzles that require you to use at least one advanced technique to solve. Some of those XY wings are so hard to see, even when you are staring right at them...lol

If anyone has some tough games from this site then maybe post the number.

I successfully used an x-wing for the first time today to solve a puzzle. I'm so proud!

They stare at me and I still can't see them....lol

It's this puzzle. Took me about an hour to finish it. Mark does it in about 6 minutes.



At the end I was gleefully knocking out cells and doing my Simon impression. "And that means that this is a 6, and this is a 1, and this is a 4, and this is a 1! It's simply gorgeous!"

Cracking the Cryptic has a kickstarter. They are putting together a greatest hits book.

It was fully funded within 24 hours. Nearly every day they have to add new stretch goals. It will also include brand new puzzles by the creators of the greatest hits.

This one took me 31 minutes.

Once Mark finishes his introduction of the video he knocks it out in 8 minutes.

https://www.youtube.com/watch?v=jV8zz0G0W6g

Has anyone backed the Kickstarter project? According to discord if you 100% definitely want to get the book then you'll have to back it on there, no guarantees otherwise.

I'm backing it because why the hell not, there will be 26 CTC selected puzzles, 26 new puzzles and 20 community selected puzzles plus 2-3 puzzle hunts so roughly 100 puzzles

I have backed it.

And not just generic workaday puzzles. These are hand-crafted by the best puzzle setters out there.

Yep, only 3 days left, they're closing in on the $150,000 stretch goal that will mean Simon/Mark will do blind solves of all the new puzzles

on sudoku.com

a really tough one.. hardest one on this site I have encountered

#858812422

I backed it. I had never heard of these guys until a week or so ago when I stumbled into this thread. I haven't decided yet if I hate you guys or love you. I've spent wayyyyy too much time solving puzzles since I discovered their channel. I'm usually an early to bed kind of guy, but now find myself trying to finish these GD puzzles at midnight/2/3am...

I didn't see a way to select a particular puzzle on the site. I just did an expert level sudoku that was fairly easy. I would like to see the one you did.

Bwah-ha-ha! And their videos are so watchable.

Sorry Eric, it was Sudoku9x9.com u should be able to enter the number..

https://sudoku9x9.com/

And they're the only clickbait titles I fall for every damn time!

I run into this once in a while (as I am sure we all do). It is always nice to find a shortcut.

In the puzzle below I got to this same spot, but spotted the 34/34/34/349 before looking for any XY wings (or more advanced) eliminators.

R6/C1 has to be a 9 or else the game has two solutions. It solved quite easy after that.

Ahh, uniqueness. Definitely an effective shortcut. Personally, I try to avoid it, as Simon does. Very common technique in the general sudoku community.