Hanamaya Puzzles, Easiest to Hardest
Heavy metal brainteasers
Hanamaya puzzles are brainteasers, the goal being to separate (or reconnect) their pieces. Designers from all over the world submit designs for puzzles and Hanamaya accepts the best to add to their line. They come in six levels of difficulty, with 1 being the easiest and 6 the hardest.
I can attest from personal experience that Level 6 puzzles are incredibly tough and generally undoable. Highly recommend!
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