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Freeslice is a technique used on big cubes ranging from 4x4 and up in which the slices between the U and D layers do not have to be re-solved immediately after an edge pair is formed. Rather, the slices are re-solved after 8 edges are paired and when there are only 4 edges are remaining to be paired.

Essentially all world-class big cube solvers use this technique to some extent.

See Also