Friendly Kings and Knights
(Published on 3. June 2026, 22:37 by Maldivia)
Normal 8x8 sudoku rules apply.
Friendly Kings and Knights:
All cells in the puzzle have exactly ONE friendly cell that is a king's or knight's move away, containing the same digit. All other cells a king's or knight's move away cannot contain the same digit.
Example: if R3C3 is a 5, exactly one of the 12 cells a king's or knight's move away (R1C[2,4], R2C[1,2,4,5], R4C[1,2,4,5], R5C[2,4]) is also a 5.
The grid virtually loops around, so first and last row/column are considered next to each other, thus R1C1 and R8C8 are considered a king's move apart.
Killer cages:
Digits inside a killer cage must sum to the digit on the top left corner of the cage. Digits do not repeat inside cages.
Solution code: Digits from row 7 (left to right).
Comments
on 9. June 2026, 00:12 by itsid
it's quite difficult to scan fully wrapping grids especially with chess moves.
But if one's observant enough it's a nice and easy puzzle.
on 5. June 2026, 03:23 by lootyloot
very fun ruleset
on 4. June 2026, 16:42 by VitP
this may seem very hard, or requiring massive bifurcation. NO. there is a fairly easy solution.
1) start by testing 2s. you can eliminate a couple candidates, but most of them just lead into a quagmire. abandon 2s for now.
2) test 1s. the 1s in box 2 are highly restricted, and suddenly the 2 pattern becomes clear.
3) with a couple digits in hand, the grid is VERY constrained.
p.s. do NOT attempt to solve the whole grid at once, unless you like banging your head on a wall.
on 4. June 2026, 03:28 by Freegerator
Neat ruleset thanks for the puzzle!
on 3. June 2026, 23:51 by dzamie
A little tricky to keep track of, but pretty fun once I worked out a system. Marking off which pairs were already friends really helped to remind myself where the anti-king/anti-knight actually came into play.
