Tag Archives: WXYZ-wing

Nakex 183 Hides the Keys


The last review puzzle, Nakamoto Extreme 183, follows the collection’s pattern of hiding easier removals behind methods that are very difficult to spot. An effective defense is to maintain bv maps, X-panels, and coloring clusters carefully as more advanced results … Continue reading

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Nakamoto 143 Avoids Extremes


Nakex 143, the eighth puzzle in the review, avoids AIC building with an outstanding exhibition of advanced techniques, and three subsets in basic line marking, including this naked triple. Two more show up in LM closing, the stage that examines … Continue reading

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Strmckr’s Double Common ALS_XZ


This post translates an instructive example from “strmckr”, an expert forum contributor, and adds some observations about double common ALS_XZ.  Then Sudent comments on some Sudoku history that Strmckr included with his example. In his comments on the April 10 … Continue reading

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A WXYZ vs. BARN Settlement


In this post, progress is reported on the Sysudoku Guide, and on  a possible territorial agreement between the WXYZ wing and the Bent family. The Guide, that link up there on the menu bar, is taken shape. The Basic pages … Continue reading

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How the BARN Was Built


This post continues a report on the discovery of a practical human solving technique and the need to have it properly classified and named. This method has been credited to its author, known by his forum moniker as StrmCkr, on … Continue reading

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Tough, But Not So Nasty


Continuing with the review of Frank Longo’s The Nastiest Sudoku Book Ever, a sysudokie faces another hard judgement on a Single Alternate Sue de Coq, in Nastiest 662. If the trial is archived, the puzzle withstands major blows before giving … Continue reading

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Longo’s Nastiest Ever Collection


This post begins the review of Frank Longo’s The Nastiest Sudoku Book Ever with a  review table and  solving highlights of two review puzzles, Nastiest 607 and 629. The original post was revised to correct errors found by my backup … Continue reading

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Please Give WXYZ Some Space


This post takes issue with recent redefinitions of the WXYZ-wing It suggests a name for Andrew Stuart’s update, apparently proposed by StrmCkr, and recalls the Bob Hanson’s Bent Naked N-set method in Student Assistant. The derivation of the toxic set … Continue reading

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An Insane 445 Pattern Slicing Demo


In this revised post, difficult line marking leaves a semi-monster. It is whittled down to a decisive double ANL, which can be duplicated instructively by pattern slicing.  The review puzzle, Insane volume 4, book 4, number 5, with thousands more, … Continue reading

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Regular XYZ-wings


This post explains how the regular XYZ-wing and WXYZ-wing make eliminations with toxic sets. Regular XYZ-wings are illustrated, and the XYZ form of the bv map is introduced. If you are following the Order of Battle, you should be returning … Continue reading

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