Of ALL the puzzles you have ever solved, what would be your all time favorite puzzle to solve?
and of ALL the puzzles you have build

what have been the most entertaining to build?
AND.. of ALL the puzzles you have ever seen, what was the most intertaining to look at (estethics)?
please answer when thought about well
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My favourite puzzler is the 3x3x3 cube
my favourite build was the Arrow Cube
and my favourite puzzle to look at must be Anthony Greenhill's Tetrahedron