Rules:
(Note: unlike normal stations and A38, the loop does not have to pass through every cell)
For aditional clarity an example of a valid grid has been given. The blue loop is the A38, the red loop is the Stations, and both loops plus the green segments froms the u-bahn. White circles have been used to mark the cells where permits are obtained for the A38 loop.
Solution code: For every column from left to right, the number of line segments heading to the right from that column.
on 17. February 2025, 19:46 by polar
Safe to say you had me eyeing up this puzzle ever since I saw the ruleset and the solve very much lives up to its satanic origin. Think I might need to go back into hibernation for a while now
on 9. February 2025, 14:27 by Silverstep
Ten days! I didn't work on it every day, but still. Longest solve I've ever done. Fairly straightforward, except for the torus topology part, which I made myself prove rigorously.
on 31. January 2025, 00:21 by Silverstep
Posting some rule clarifications re: the A38 area that I got over discord, for archival purposes
* You're not allowed to skip an A38 clue: if the clue says X you must visit at least X cells around it. The Xth cell must not overlap with an asterisk. Upon visiting this cell, the number of permits you have changes from zero to one. (And every asterisk you visit changes that from one to zero).
* The Xth cell of clue X can overlap with the Yth cell of clue Y, which is allowed. In this case you obtain only one permit there.
* There must be no leftover permits when the traveller gets back to the starting black circle.
on 26. January 2025, 19:09 by ONeill
This is the craziest and longest puzzle I’ve ever done, I really have no idea how you put this together but the solution path is awesome and brutally difficult for the entirety of the solve. Very well done! and thanks for the torture
on 19. January 2025, 00:57 by The Book Wyrm
Fixed example image
on 15. January 2025, 13:53 by Agent
Thanks very much for this gift, Book Wyrm! It was a very challenging and equally satisfying solve, and a truly memorable experience.
And I have to say, what a ruleset, it's the first time I saw a toroidal permaculture, and that's already a very interesting concept.