Solution code: Box 1, in reading order. 9 digits no spaces.
on 19. July 2025, 04:36 by Nemefish
The break in was a bit of a struggle. If you are stuck look below
The corner thermos in box 1 and box 3 are important and help with a large swath of the perimeter.
on 7. July 2025, 22:20 by Exigus
Very nice puzzle. Seems quite hard at first but once you poke it a bit it opens up. Thanks!
on 6. July 2025, 07:14 by PhysicistFromFunen
Changed the estimated difficulty level.
on 6. July 2025, 00:48 by VitP
this one is definitely level 4.
you need to be an expert BOTH at yin-yang AND parity thermos to even get started, and that gives you virtually nothing.
there is basically NO information to even try the yin-yang.
AND THEN there is the ADMINISTRATIVE problem that you need TWO TYPES of colouring, i.e. the available notation is insufficient.
HOWEVER, i AM a fan of both genres, so i did massive bifurcation until i found the simple pattern that leads to a fast solve.
SPOILER/HINT: it is the two puny thermos in the corners. didn't see that coming.
thanks to PfF for another stellar puzzle.
—- PFF:
Thank you for the comment - I definitely see your points!
Regarding the double colouring, I found that using light and dark grey for parity did not obstruct the clarity of the yin yang. But I appreciate that that may well just be an effect of setter’s glasses and that I am a sucker for colouring puzzles ;)
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