Tag Archives: kraken X-wing

UHC 177 Introduces a Beeby Option

This post gets left page ultrahardcore 177 to coloring with an interesting Sysudoku Basic and a kraken X-wing accessed with a recently added AIC option. Stefan Heine’s ultrahardcore 177 makes many left page concessions, but makes a fight of it. … Continue reading

Posted in Advanced Solving, Puzzle Reviews, Heine | Tagged , , , , | Leave a comment

Fleshing Out Stuart’s ALS Node Figure 30.1

Andrew Stuart’s The Logic of Sudoku, in a chapter on Almost Locked Sets, presents an example of an ALS node in a confirming Almost Nice Loop, as Figure 30.1. This post fills in the solution, before and after the series … Continue reading

Posted in Advanced Solving, Expert Reviews, Stuart | Tagged , , , , , , | Leave a comment

A Little Harder Ardson v2. 358

Next to last, and getting beyond the XY railway, is A.D. Ardson Very Hard, v.2 358. Here is the basic trace, including an X-wing in the close of line marking. The column 6-wing  was found in line marking closure, when … Continue reading

Posted in Advanced Solving, Puzzle Reviews | Tagged , , , , , | Leave a comment

Berthier’s xyzt Chain

This post concludes my reading of Denis Berthier’s The Hidden Logic of Sudoku, with two example puzzles to illustrate his xyzt-chain. While it is good to be aware of Berthier’s “t” versions of classic XY chains, I don’t recommend a comprehensive … Continue reading

Posted in Advanced Solving, Berthier, Expert Reviews, Extreme Solving | Tagged , , , , | Leave a comment