Read the Sudoku help page for the rules, and the techniques potentially required to solve BrainBashers Sudoku.
Remote Pairs is an advanced technique. Its name comes from a collection of locked pairs that are linked together remotely. The simplest way to picture them is to form a path through an even number of locked pairs (i.e. an even number of squares containing locked pairs). The intersection of both ends of the path cannot contain either of the digits in the locked pair. The path may consist of two, three or more locked pairs (i.e. 4, 6 or more squares) and the intersection might be on a row, a column or in a 3x3 block.
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