Rules:
Normal Sudoku rules apply.
Digits along an arrow must sum to the digit in that arrow's bulb.
All arrow cells (including bulbs) act as fortress (maximum) cells: Cells on an arrow or bulb must be larger than all orthogonal neighbors of the cell that are not on an arrow or bulb.
Solution code: Column 5
on 10. February 2026, 22:51 by Motty
Very nice! One of the most minimalist puzzles I've seen.
on 29. January 2026, 21:08 by dawidk
A unique yet fascinating combination of two rules. Well done.
on 29. January 2026, 08:00 by silent_rob
Thanks for such a lovely puzzle! Discovering the deductions that could be made with the fortress arrows throughout the puzzle made this a pleasure to solve.
on 28. January 2026, 20:45 by BrianO
Very nice! I initially skimmed the rules and thought it was only the bulbs that acted like fortress cells. I stared for a bit and realized I couldn't possibly solve it. Once I went back, the opening unfolded beautifully. Reading is fundamental! :P
on 28. January 2026, 20:11 by MiguelMunoz
Fortress rule was very novel and interesting!
on 25. January 2026, 19:59 by wuc
Great puzzle. Awesome break in. One tough step near end to me. Almost lost it there. Brilliant setting thx.
on 25. January 2026, 19:50 by brskri
The fortress restriction in combination with the arrows is way more powerful than it first appears. Nice puzzle!
on 25. January 2026, 04:32 by Crusader175
Fun idea and puzzle!
on 24. January 2026, 23:44 by Jolly Rogers
Great setting, satisfying unravel and the last little deduction was the cherry on top, thanks!
on 24. January 2026, 21:39 by Qodec
Very cool concept. Impressed with how you made it work!
on 24. January 2026, 16:19 by Franjo
Thank you very much for creating and sharing another beautiful puzzle with perfect setting. Amazing!
on 24. January 2026, 09:48 by tomer
Nice one! Idea for the next one - arrows that each one acts like a minimum cell
on 24. January 2026, 07:10 by antiknight
Amazing that this solves! Loved it
on 24. January 2026, 03:31 by PinkNickels
I've solved a lot of puzzles and never seen one quite like this. Very nice execution of an old idea applied in a new way. Impressive setting! Bravo
Please note: The German version of this page has changed. It is possible that this page does not contain the latest information.