Category Archives: Advanced Solving

Techniques applying after candidates are identified. Why they work. How and when to look for them.

The Complex 1-Way in AIC Building


This post is about an AIC building option offered by Philip Beeby’s PhilsFolly.com solver, and how and where it is best applied in DIY solving.  Here we refer to this solver as Beeby and this technique as complex 1-way.  Complex … Continue reading

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Ultrahardcore Review ALS-wings V


This post completes a survey of ALS-wings in the review of Stefan Heine’s ultrahardcore collection. The study was to determine how ALS-wings can be constructed as ALS maps are built. This post covers five more examples in UHC 443 found … Continue reading

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Ultrahardcore Review ALS-wings IV


The survey of ALS-wings in the ultrahardcore review continues, with new wing building situations, another ALS version of the Death Blossom, and an amazing ALS. In this UHC 267 ALS-wing it’s a two box ALS , connected by a column … Continue reading

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Ultrahardcore Review ALS-wings III


This post’s examples from UHC 179 include ALS-wings with bv cells, and uncover two essential facts about ALS value groups. This post’s examples include ALS-wings with bv cells, and uncover two essential facts about ALS value groups. Instead of following … Continue reading

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An ALS_XZ Wrap Up of UHC 311


This post shows what it means to maintain three three ALS maps. ALS map updates are followed through a series of  ALS_XZ until a decisive coloring wrap on Stefan Heine’s ultrahardcore 311. We are exploring ALS mapping as ALS_XZ scans … Continue reading

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AIC Building Trial Follow Up for UHC 311


This post returns to AIC building after an encounter with a spontaneous ALS led to expanded coloring and a color trial. That will be normal under a plan of incremental ALS mapping. The confirmation of red had the follow up … Continue reading

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Dov Introduces Lite Coloring of ultrahardcore 311


This post finishes the lite coloring revisit of past trials with Dov Mittelman’s lite introduction. It leads to a solution of Stefan Heine’s UHC 311 without trial. This puzzle occupied 3 posts in the ultrahardcore review, starting with November 3. … Continue reading

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Lite Coloring Avoids Trials in KrazyDad 425


This post backs up your lite coloring effort, I hope, on KrazyDad 425. The initial lite trees deliver a cluster merge, and as these grow, lite coloring gives two confirmations and a coloring wrap to finish without trial. The first … Continue reading

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A Lite Update on Castillo’s Only Extreme 347


This post updates a solution by coloring trial in the review post of 12/19/17. A bypass of 6 4-fills resolves 3 of them immediately,  but goes no further than the original 3-fill only bypass.  Then we follow Beeby through a … Continue reading

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A Lite Coloring Update of Castillo’s Only Extreme 261


This post is the first of several which update earlier review solutions to include a new guy in town, lite coloring. The earlier posts will be left as they are, except for added links to these updating posts. Instead of … Continue reading

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