Today includes two of the three Semi-Final A puzzles, ending with this one. The third puzzle in the semi-final will be posted tomorrow.

PDF

or solve online in Penpa, or also solve online in SudokuPad as a new option (note: highly recommended to turn off “Mark Solved Digits” option if you use that in SudokuPad).

Author/Opus: This is the 15th puzzle from guest contributor Clover.

Rules: This Sudoku does not have a unique solution for the full grid (it actually has a large number of solutions), but there is exactly one cell in which a number can be logically placed that is fixed across all solutions. Find this cell and its unique value.

This puzzle follows Even/Odd Sudoku rules, so no number repeats in any row, column, or bold region. Cells with a square must contain an even number; cells with a circle must contain an odd number.

Time Standards: This competition had 1-point (easy), 2-point (medium), 3-point (hard), or higher value puzzles. This would have been 2 points (medium category), roughly 1.5-2 minute target.

Solution: PDF

Note: Follow this link for other Just One Cell Sudoku.

Note 2: Comments on the blog are great! For a more interactive discussion, please also consider using our Just One Cell Sudoku Discussion post on the GMPuzzles Discord. Not a member of the Discord? Click this link for basic access.

Today includes two of the three Semi-Final A puzzles, starting with this one. The third puzzle in the semi-final will be posted tomorrow.

PDF

or solve online in Penpa, or also solve online in SudokuPad as a new option (note: highly recommended to turn off “Mark Solved Digits” option if you use that in SudokuPad).

Author/Opus: This is the 574th puzzle from Thomas Snyder, aka Dr. Sudoku.

Rules: This Sudoku does not have a unique solution for the full grid (it actually has a large number of solutions), but there is exactly one cell in which a number can be logically placed that is fixed across all solutions. Find this cell and its unique value.

This puzzle follows Classic Sudoku rules, so no number repeats in any row, column, or bold region.

Time Standards: This competition had 1-point (easy), 2-point (medium), 3-point (hard), or higher value puzzles. This would have been 2 points (medium category), roughly 1.5-2 minute target.

Solution: PDF

Note: Follow this link for other Just One Cell Sudoku.

Note 2: Comments on the blog are great! For a more interactive discussion, please also consider using our Just One Cell Sudoku Discussion post on the GMPuzzles Discord. Not a member of the Discord? Click this link for basic access.

This is the last of three extra Just One Cell puzzles posting today. Enjoy!

PDF

or solve online in Penpa, or also solve online in SudokuPad as a new option (note: highly recommended to turn off “Mark Solved Digits” option if you use that in SudokuPad).

Author/Opus: This is the 14th puzzle from guest contributor Clover.

Rules: This Sudoku does not have a unique solution for the full grid (it actually has a large number of solutions), but there is exactly one cell in which a number can be logically placed that is fixed across all solutions. Find this cell and its unique value.

This puzzle follows Killer Sudoku rules, so no number repeats in any row, column, or bold region. The sum of the digits in each cage must equal the value given in the upper-left corner of that cage. Digits cannot repeat inside a cage.

Time Standards: This competition had 1-point (easy), 2-point (medium), 3-point (hard), or higher value puzzles. This would have been 4 points (very hard category), roughly 4-5 minute target.

Solution: PDF

Note: Follow this link for other Just One Cell Sudoku.

Note 2: Comments on the blog are great! For a more interactive discussion, please also consider using our Just One Cell Sudoku Discussion post on the GMPuzzles Discord. Not a member of the Discord? Click this link for basic access.

This is the second of three extra Just One Cell puzzles posting today. Enjoy!

PDF

or solve online in Penpa, or also solve online in SudokuPad as a new option (note: highly recommended to turn off “Mark Solved Digits” option if you use that in SudokuPad).

Author/Opus: This is the 13th puzzle from guest contributor Clover.

Rules: This Sudoku does not have a unique solution for the full grid (it actually has a large number of solutions), but there is exactly one cell in which a number can be logically placed that is fixed across all solutions. Find this cell and its unique value.

This puzzle follows Kropki Pairs Sudoku rules, so no number repeats in any row, column, or bold region. If a white circle is given between two adjacent cells, then the two numbers in those cells must differ by 1. If a black circle is given between two adjacent cells, then the two numbers must have a ratio of 2. Pairs of cells without circles can have any relationship.

Time Standards: This competition had 1-point (easy), 2-point (medium), 3-point (hard), or higher value puzzles. This would have been 2 points (medium category), roughly 1.5-2 minute target.

Solution: PDF

Note: Follow this link for other Just One Cell Sudoku.

Note 2: Comments on the blog are great! For a more interactive discussion, please also consider using our Just One Cell Sudoku Discussion post on the GMPuzzles Discord. Not a member of the Discord? Click this link for basic access.

This is the first of three extra Just One Cell puzzles posting today. Enjoy!

PDF

or solve online in Penpa, or also solve online in SudokuPad as a new option (note: highly recommended to turn off “Mark Solved Digits” option if you use that in SudokuPad).

Theme: One More Slice of Pi

Author/Opus: This is the 3rd puzzle from guest contributor Philip Newman.

Rules: This Sudoku does not have a unique solution for the full grid (it actually has a large number of solutions), but there is exactly one cell in which a number can be logically placed that is fixed across all solutions. Find this cell and its unique value.

This puzzle follows Classic Sudoku rules, so no number repeats in any row, column, or bold region.

Time Standards: This competition had 1-point (easy), 2-point (medium), 3-point (hard), or higher value puzzles. This would have been 1 point (easy category), roughly 0.75-1 minute target.

Solution: PDF

Note: Follow this link for other Just One Cell Sudoku.

Note 2: Comments on the blog are great! For a more interactive discussion, please also consider using our Just One Cell Sudoku Discussion post on the GMPuzzles Discord. Not a member of the Discord? Click this link for basic access.

The 24 main puzzles for the Just One Cell Competition at SudokuCon that have been featured over the last two weeks are here:

Qualifier Test PDF

Qualifier Solutions PDF

After 36 minutes, there was one perfect finisher and several other high scores on that qualifier that moved onto the playoffs where two groups of four matched up to determine a final four and then just one winner. Starting tomorrow we will feature the semifinal puzzles, while today we have some extras kept as back-ups.

While our Just One Cell posts end on June 6th, we have some exciting things coming June 7th, so keep coming back to see what is next for the future of Sudoku on GMPuzzles.