In creating a sliding pieces puzzle, we tried the extreme; move one piece of twelve dominoes from the upper left corner to the lower right in a 5x5 tray. This
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Next best, eleven dominoes gave a wealth of puzzles from moderate to very difficult. We christened this puzzle Daunting Dominoes and present it with plenty of challenges needing 33 to as much as 119 moves to complete.
The challenges can be found here:
https://ddchallenges.blogspot.com/
The puzzle comes with a lid and with a size of 87x87x15mm (3.43x3.43x0.59") it is compact enough for travel while guaranteeing a perpetuity of puzzling pleasure.