This puzzle was created by Jakhob and wooferzfg. It is a variant of U-Bahn with empty cell clues, which originates from a series by KNT.
If you are unfamiliar with U-Bahn, here is a guide that covers the core logic.
Draw a loop network through the centers of some cells, which may branch or turn, but may not have any dead ends.
A clue outside the grid indicates in how many cells the corresponding behavior (i.e. turn, straight line, branch, cross, or unvisited) occurs in the row or column, irrespective of rotation.
Solution code: For each column except the last, from left to right, the number of lines leading to the right from that column
on 16. September 2024, 18:58 by zetamath
A very worthy tribute to my favorite ubahn series by KNT. Great puzzle, and actually I'd put this at 4 stars, I didn't even break it once!
on 12. June 2024, 16:34 by zzw
Awesome puzzle! Really cool breakin and lots of fun throughout.
on 1. September 2023, 08:17 by Agent
Fantastic puzzle, thanks!
on 7. August 2023, 12:02 by Statistica
Wow! Raffiniert und sehr (schön) schwierig.
on 3. August 2023, 22:04 by Myxo
Really cool puzzle!
on 3. August 2023, 00:33 by Piatato
Awesome puzzle, thanks!
on 31. July 2023, 14:25 by ONeill
Very clever puzzle :)
on 30. July 2023, 16:27 by polar
Beautiful! Thanks
on 30. July 2023, 05:07 by KNT
I'm a huge fan of this variation of the genre, thanks for making this... fun puzzle! I must also add that there is a step in the middle that is absolutely top class, other solvers will definitely know what I am referring to.