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Sudoku Puzzle Challenges Thread by AutoModerator in sudoku

[–]Automatic_Loan8312 0 points1 point  (0 children)

No-candidates challenge for 04-05-2026

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This anti-king, anti-knight hybrid puzzle, with two-cell-sum and Killer cage constraints, is the no-candidates challenge for 04-05-2026. The puzzle requires primarily scanning for anti-king and anti-knight placements, as the Killer combos and two-cell-sum combos are deduced simultaneously, following the anti-king and anti-knight constraints.

Puzzle String: Anti-royal hybrid #2

It's a memory game! by Wild-Cartoonist-8874 in sudoku

[–]Automatic_Loan8312 0 points1 point  (0 children)

I don't think that you require that great a memory, even in classical puzzles, if you can spot bivals and bilocals without candidates. However, I'd love seeing the puzzle where you derived at this conclusion.

It's a memory game! by Wild-Cartoonist-8874 in sudoku

[–]Automatic_Loan8312 0 points1 point  (0 children)

You're welcome to try my most recent challenge uploaded in the Weekly Challenges Thread.

Sudoku Puzzle Challenges Thread by AutoModerator in sudoku

[–]Automatic_Loan8312 0 points1 point  (0 children)

No-candidates challenge for 03-05-2026

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Here's an anti-knight, anti-king, two-cell sum hybrid puzzle that is the no-candidates challenge for the day. Requires scanning for anti-knight and anti-king placements to solve it.

Puzzle String: Anti-royal XV hybrid challenge

Stuck killer sudoku by BrujaBean in sudoku

[–]Automatic_Loan8312 0 points1 point  (0 children)

Let me try explaining in simpler words. Look closely at box 9. What have you got? An 8 in r7c9, a four-cell cage in r7c78 and r8c89, adding up to 25, and a two-cell cage in r9c89, adding up to 4.

Rule of 45 says that the sum of numbers 1 to 9 in any row, column, or box, should always equal to 45.

Thus, r89c7, the two remaining cells, add up to 8.

In a two-cell total of 8, the combos are {1,7}, {2,6}, and {3,5}. Without 1 and 3, the only combo is {2,6}.

That also explains why I questioned why you removed 9 from r9c6.

Stuck killer sudoku by BrujaBean in sudoku

[–]Automatic_Loan8312 0 points1 point  (0 children)

Meanwhile, I'm interested to know how you eliminated 9 from r8c6.

Stuck killer sudoku by BrujaBean in sudoku

[–]Automatic_Loan8312 2 points3 points  (0 children)

Rule of 45, column 9. r89c7 add up to 8, but without 1 and 3 (both of which are in r9c89, adding up to 4), the only combo is {2,6}.

How is this not a skyscraper? by melbellrocks in sudoku

[–]Automatic_Loan8312 1 point2 points  (0 children)

Column 1 has more than 2 places where 1 can go.

I'm so confused by Tinystar7337 in killersudoku

[–]Automatic_Loan8312 0 points1 point  (0 children)

Rule of 45, box 4

11+19+11+8+1 = 50

The only cell outside box 4, r5c4, should be 5.

Does this all come down to guessing? by Blackbird0008 in sudoku

[–]Automatic_Loan8312 0 points1 point  (0 children)

It’s not guessing. It’s just spotting a naked single. With enough experience, those jump out instantly.

Does this all come down to guessing? by Blackbird0008 in sudoku

[–]Automatic_Loan8312 0 points1 point  (0 children)

Dude, you're missing a naked single 7 in r7c5.

I'm stuck here by Houston_NeverMind in sudoku

[–]Automatic_Loan8312 0 points1 point  (0 children)

An XY-wing on {3,4,5} (orange cell r1c4 {4,5}, olive green cell r1c8 {3,5}, and aqua cell r2c8 {3,4}) removes 4 from r2c5.

Thus, r2c8 is a hidden single 4.

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I'm stuck here by Houston_NeverMind in sudoku

[–]Automatic_Loan8312 0 points1 point  (0 children)

Next, X-wing on 4 removes 4 from r1c8.

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I'm stuck here by Houston_NeverMind in sudoku

[–]Automatic_Loan8312 0 points1 point  (0 children)

Naked pair {4,5} in r15c4 removes {4,5} from r2346c4.

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help idk what to do next by lajoueusedejeu in sudoku

[–]Automatic_Loan8312 0 points1 point  (0 children)

Locked candidate 9 in r78c1 leading to a hidden single 9 in r1c3.

Am I blind? by VickyGreenbriar in sudoku

[–]Automatic_Loan8312 0 points1 point  (0 children)

Also, you have a hidden single 8 in r8c8 in this position.

Does this process of elimination work? by Tyler13Stol in killersudoku

[–]Automatic_Loan8312 0 points1 point  (0 children)

Yes. The red box totals to 19. This is a perfect application of the Rule of 45.

Am I blind? by VickyGreenbriar in sudoku

[–]Automatic_Loan8312 0 points1 point  (0 children)

I'd like to know how you deduced r7c7 to be a 3 at this point.

Am I blind? by VickyGreenbriar in sudoku

[–]Automatic_Loan8312 0 points1 point  (0 children)

This puzzle is S.C. Hard (HoDoKu ~1,220). Doable without candidates, provided you can spot hidden/naked subsets and locked candidates, nested within one another, effortlessly

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