Color Wrap
Color Wrap is a subtype of coloring that eliminates candidates for one of the parities in a single cluster by exposing a contradiction in that parity. The candidates with the opposite parity can be placed in their respective cells, making this a placement technique, rather than an elimination technique.
Color Wrap belongs to Simple Colors, together with Color Trap.
Every coloring move can easily be replicated by a chain. However, colors are easier to use by most players, because it is a more visual technique.
Here is an example:
All the candidates for digit 1 are highlighted. All but one of them belong to a large cluster of conjugate pairs. The 2 parities in this cluster have the colors green and blue. All candidates with the same color are equivalent, which means that they either all contain digit 1 or none of them contains digit 1. In other words: they are true or false as a group.
In the example, it is impossible for the blue candidates to be true together, because that would cause conflicts in row 1, column 5 and box 2. The only remaining alternative is that all green colors are true. We can place digit 1 in all the green cells.
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