That was the time of my first ever 12x12x12 solve, took a bit longer than I expected but once I had finished the centres it was almost over as the edges don't take long at all, as cubes get bigger, the centres take up a bigger and bigger part of the solve, for 12x12x12 the ratio is roughly 4:1 for centres:rest of solve whereas for 7x7x7 it is 1:1 on average I would say. If anyone has any challenge ideas then please let me know.

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