Murder mystery sudoku — the daily cases for 22 September 2026

Every detective in the world got these same crime scenes on 2026-09-22 — each difficulty published twice, once untimed and once as time attack. Each case is procedurally generated and then proved to have exactly one logical solution before it is published, including the cases where somebody is lying. You place every suspect back on the map using only their testimony: exactly one person per row, never two in a column. Whoever is left alone with the victim did it.

Beginner — The Bunker

A 5×5 grid across 4 rooms: Watchtower, Pantry, Generator Room, Hydroponics. Seven statements, five squares nobody could stand on, and enough testimony that the surplus is what pins the last two down.

Cracked by 21 detectives so far.

How this case was cracked — the full solution to this board, step by step

Every step below is the solver’s own — the same one that proved this board has exactly one answer. The counts are real: you can check them against the grid.

Lettered squares are objects. Most take the square out of play — which is why the counts above are of free squares, not of all of them — but the ones marked below do not: their square is still in play. B — bed (square stays free) · C — cabinet · G — garbage can · WD — wooden table · WO — wooden chair (square stays free)

The testimony

What each person said, and how much of the board it rules out.

Paloma was in column 3. leaves 3 of 22 squares
Show it on the board
The squares this one statement leaves Paloma: 3 of 22.
Paloma was in the hydroponics bay. leaves 2 of 22 squares
Show it on the board
The squares this one statement leaves Paloma: 2 of 22.
Dante was in the bottom row. leaves 3 of 22 squares
Show it on the board
The squares this one statement leaves Dante: 3 of 22.
Dante was in the generator room. leaves 1 of 22 squares
Show it on the board
The squares this one statement leaves Dante: 1 of 22.
Sol was in row 2. leaves 5 of 22 squares
Show it on the board
The squares this one statement leaves Sol: 5 of 22.
Sol was in the pantry. leaves 1 of 22 squares
Show it on the board
The squares this one statement leaves Sol: 1 of 22.
Vasco was in the watchtower. leaves 5 of 22 squares

Show the squares Paloma had left

The squares still open to Paloma once their own statements are taken into account — 2 of 22.

What the testimony settles on its own

Nobody shares a row or a column, so each placement narrows everyone else. Before a single guess:

Enzo can only be in Pantry (row 1, column 2) — down from 22 possible squares.
Paloma can only be in Hydroponics (row 3, column 3) — down from 2 possible squares.
Vasco can only be in Watchtower (row 4, column 4) — down from 5 possible squares.

The answer

That leaves one arrangement, and one person who could have done it: Sol, in Pantry (row 2, column 5).

Show the solved board

The only arrangement the testimony allows. Sol is ringed in red.

Beginner · time attack — The Bunker

A 5×5 grid across 3 rooms: Shelter, Airlock, Workroom. Seven statements, six squares nobody could stand on, and enough testimony that the surplus is what pins the last two down.

Cracked by 6 detectives so far.

How this case was cracked — the full solution to this board, step by step

Every step below is the solver’s own — the same one that proved this board has exactly one answer. The counts are real: you can check them against the grid.

Lettered squares are objects. Most take the square out of play — which is why the counts above are of free squares, not of all of them — but the ones marked below do not: their square is still in play. B — bed (square stays free) · CA — cabinet · CO — computer · CR — carpet (square stays free) · CT — crate · G — garbage can

The testimony

What each person said, and how much of the board it rules out.

Boris was in the rightmost column. leaves 5 of 21 squares
Show it on the board
The squares this one statement leaves Boris: 5 of 21.
Boris was in the top row. leaves 1 of 21 squares
Show it on the board
The squares this one statement leaves Boris: 1 of 21.
Sofia was in row 3. leaves 4 of 21 squares
Show it on the board
The squares this one statement leaves Sofia: 4 of 21.
Sofia was in column 2. leaves 1 of 21 squares
Show it on the board
The squares this one statement leaves Sofia: 1 of 21.
Gilda was in column 4. leaves 3 of 21 squares
Show it on the board
The squares this one statement leaves Gilda: 3 of 21.
Abel was in the airlock. leaves 9 of 21 squares
Abel was in row 4. leaves 3 of 21 squares
Show it on the board
The squares this one statement leaves Abel: 3 of 21.

Show the squares Gilda had left

The squares still open to Gilda once their own statements are taken into account — 3 of 21.

What the testimony settles on its own

Nobody shares a row or a column, so each placement narrows everyone else. Before a single guess:

Gilda can only be in Airlock (row 2, column 4) — down from 3 possible squares.
Ivan can only be in Shelter (row 5, column 1) — down from 21 possible squares.
Abel can only be in Airlock (row 4, column 3) — down from 3 possible squares.

The answer

That leaves one arrangement, and one person who could have done it: Sofia, in Shelter (row 3, column 2).

Show the solved board

The only arrangement the testimony allows. Sofia is ringed in red.

Easy — The Bunker

A 6×6 grid across 5 rooms: Airlock, Hydroponics, Shelter, Watchtower, Pantry. Seven statements, nine squares nobody could stand on, and no assumption anywhere: elimination alone closes it.

Cracked by 18 detectives so far.

How this case was cracked — the full solution to this board, step by step

Every step below is the solver’s own — the same one that proved this board has exactly one answer. The counts are real: you can check them against the grid.

Lettered squares are objects. Most take the square out of play — which is why the counts above are of free squares, not of all of them — but the ones marked below do not: their square is still in play. B — bed (square stays free) · CO — computer · CR — crate · F — floor lamp · G — garbage can · R — radio · S — stove · W — wooden table

The testimony

What each person said, and how much of the board it rules out.

Wanda was in the watchtower. leaves 9 of 28 squares
Show it on the board
The squares this one statement leaves Wanda: 9 of 28.
Vivienne was in the leftmost column. leaves 5 of 28 squares
Show it on the board
The squares this one statement leaves Vivienne: 5 of 28.
Nestor was in the watchtower. leaves 9 of 28 squares
Show it on the board
The squares this one statement leaves Nestor: 9 of 28.
Nestor was in column 4. leaves 1 of 28 squares
Show it on the board
The squares this one statement leaves Nestor: 1 of 28.
Yolanda was beside the wooden table. leaves 1 of 28 squares
Show it on the board
The squares this one statement leaves Yolanda: 1 of 28.
Bianca was in the pantry. leaves 4 of 28 squares
Show it on the board
The squares this one statement leaves Bianca: 4 of 28.
Nobody was in the shelter.

Show the squares Bianca had left

The squares still open to Bianca once their own statements are taken into account — 4 of 28.

What the testimony settles on its own

Nobody shares a row or a column, so each placement narrows everyone else. Before a single guess:

Wanda can only be in Watchtower (row 1, column 2) — down from 9 possible squares.
Vivienne can only be in Airlock (row 6, column 1) — down from 5 possible squares.
Bianca can only be in Pantry (row 4, column 3) — down from 4 possible squares.
Percy can only be in Airlock (row 5, column 5) — down from 28 possible squares.

The answer

That leaves one arrangement, and one person who could have done it: Vivienne, in Airlock (row 6, column 1).

Show the solved board

The only arrangement the testimony allows. Vivienne is ringed in red.

Easy · time attack — The Bunker

A 6×6 grid across 5 rooms: Dormitory, Radio Room, Generator Room, Pantry, Airlock. Eight statements, ten squares nobody could stand on, and no assumption anywhere: elimination alone closes it.

Cracked by 3 detectives so far.

How this case was cracked — the full solution to this board, step by step

Every step below is the solver’s own — the same one that proved this board has exactly one answer. The counts are real: you can check them against the grid.

Lettered squares are objects. Most take the square out of play — which is why the counts above are of free squares, not of all of them — but the ones marked below do not: their square is still in play. CA — cabinet · CO — computer · CR — carpet (square stays free) · CT — crate · F — floor lamp · G — garbage can · P — potted plant · R — radio · WD — wooden table · WO — wooden chair (square stays free)

The testimony

What each person said, and how much of the board it rules out.

Katia was in the bottom row. leaves 6 of 28 squares
Show it on the board
The squares this one statement leaves Katia: 6 of 28.
Katia was in column 4. leaves 1 of 28 squares
Show it on the board
The squares this one statement leaves Katia: 1 of 28.
Julia was beside the garbage can. leaves 3 of 28 squares
Show it on the board
The squares this one statement leaves Julia: 3 of 28.
Margot was in row 2. leaves 5 of 28 squares
Show it on the board
The squares this one statement leaves Margot: 5 of 28.
Margot was beside the garbage can. leaves 1 of 28 squares
Show it on the board
The squares this one statement leaves Margot: 1 of 28.
Boris was in the leftmost column. leaves 5 of 28 squares
Show it on the board
The squares this one statement leaves Boris: 5 of 28.
Quentin was in the pantry. leaves 5 of 28 squares
Quentin was in column 3. leaves 1 of 28 squares

Show the squares Julia had left

The squares still open to Julia once their own statements are taken into account — 3 of 28.

What the testimony settles on its own

Nobody shares a row or a column, so each placement narrows everyone else. Before a single guess:

Julia can only be in Generator Room (row 3, column 6) — down from 3 possible squares.
Simon can only be in Dormitory (row 4, column 2) — down from 28 possible squares.
Boris can only be in Dormitory (row 5, column 1) — down from 5 possible squares.

The answer

That leaves one arrangement, and one person who could have done it: Boris, in Dormitory (row 5, column 1).

Show the solved board

The only arrangement the testimony allows. Boris is ringed in red.

Medium · time attack — The Bunker

An 8×7 grid across 5 rooms: Shelter, Airlock, Workroom, Generator Room, Radio Room. Twelve statements, eleven squares nobody could stand on, and one round of assume-and-test after elimination ran dry.

Cracked by 2 detectives so far.

How this case was cracked — the full solution to this board, step by step

Every step below is the solver’s own — the same one that proved this board has exactly one answer. The counts are real: you can check them against the grid.

Lettered squares are objects. Most take the square out of play — which is why the counts above are of free squares, not of all of them — but the ones marked below do not: their square is still in play. CA — carpet (square stays free) · CO — computer · F — floor lamp · G — garbage can · P — potted plant · R — radio · S — stove · WD — wooden table · WO — wooden chair (square stays free)

The testimony

What each person said, and how much of the board it rules out.

Zeno was in the same column as the floor lamp. leaves 6 of 47 squares
Show it on the board
The squares this one statement leaves Zeno: 6 of 47.
Zeno was in the same room as Rita.
Victor was in the rightmost column. leaves 6 of 47 squares
Show it on the board
The squares this one statement leaves Victor: 6 of 47.
Victor was in the top row. leaves 1 of 47 squares
Show it on the board
The squares this one statement leaves Victor: 1 of 47.
Dora was on the carpet. leaves 4 of 47 squares
Show it on the board
The squares this one statement leaves Dora: 4 of 47.
Dora was beside the wooden table. leaves 1 of 47 squares
Show it on the board
The squares this one statement leaves Dora: 1 of 47.
Lidia was not touching the outer wall. leaves 23 of 47 squares
Lidia was in the same room as Kira.
Lidia was somewhere west of Kira.
Kira was in the same column as the potted plant. leaves 5 of 47 squares
Show it on the board
The squares this one statement leaves Kira: 5 of 47.
Rita was in the western half of the scene. leaves 24 of 47 squares
Rita was somewhere north of Zeno.

Show the squares Kira had left

The squares still open to Kira once their own statements are taken into account — 5 of 47.

The squares that had to be tested

The rest does not fall out on its own. It takes 34 eliminations of the same move: put someone on a square, follow the consequences, and watch the board contradict itself.

Had Zeno stood in Generator Room (row 3, column 4), Rita would have had nowhere left to stand. So not there.
Had Bianca stood in Shelter (row 2, column 1), Lidia would have had nowhere left to stand. So not there.
Had Lidia stood in Airlock (row 6, column 2), Kira would have had nowhere left to stand. So not there.
Put Kira in Airlock (row 4, column 3) and the testimony cannot be satisfied at all. So not there.

Show what goes wrong

Suppose Zeno stood on the dashed square. Rita then has nowhere left to stand: every square still open to them is shaded out.

Another 30 squares fell the same way.

The answer

That leaves one arrangement, and one person who could have done it: Victor, in Radio Room (row 1, column 8).

Show the solved board

The only arrangement the testimony allows. Victor is ringed in red.

Medium — The Bunker

An 8×7 grid across 6 rooms: Generator Room, Hydroponics, Radio Room, Dormitory, Shelter, Airlock. Nine statements, eleven squares nobody could stand on, almost as many rooms as suspects, so a room claim nearly names a square, and one round of assume-and-test after elimination ran dry.

Cracked by 13 detectives so far.

How this case was cracked — the full solution to this board, step by step

Every step below is the solver’s own — the same one that proved this board has exactly one answer. The counts are real: you can check them against the grid.

Lettered squares are objects. Most take the square out of play — which is why the counts above are of free squares, not of all of them — but the ones marked below do not: their square is still in play. CA — cabinet · CO — computer · CR — carpet (square stays free) · CT — crate · F — floor lamp · R — radio · S — stove · WD — wooden table · WO — wooden chair (square stays free)

The testimony

What each person said, and how much of the board it rules out.

Simon was in the hydroponics bay. leaves 10 of 47 squares
Show it on the board
The squares this one statement leaves Simon: 10 of 47.
Dorian was in the same row as the crate. leaves 6 of 47 squares
Show it on the board
The squares this one statement leaves Dorian: 6 of 47.
Dorian was in column 4. leaves 1 of 47 squares
Show it on the board
The squares this one statement leaves Dorian: 1 of 47.
Rita was in the dormitory or in the airlock. leaves 18 of 47 squares
Show it on the board
The squares this one statement leaves Rita: 18 of 47.
Rita was in the same column as the computer. leaves 3 of 47 squares
Show it on the board
The squares this one statement leaves Rita: 3 of 47.
Irene was beside the floor lamp. leaves 1 of 47 squares
Show it on the board
The squares this one statement leaves Irene: 1 of 47.
Julian was in the same room as Marco.
Julian was beside the wooden chair. leaves 3 of 47 squares
Marco was somewhere east of Julian.

Show the squares Rita had left

The squares still open to Rita once their own statements are taken into account — 3 of 47.

The squares that had to be tested

The rest does not fall out on its own. It takes 13 eliminations of the same move: put someone on a square, follow the consequences, and watch the board contradict itself.

Had Simon stood in Hydroponics (row 1, column 5), Rita would have had nowhere left to stand. So not there.
Had Rita stood in Airlock (row 5, column 5), Marco would have had nowhere left to stand. So not there.
Put Julian in Generator Room (row 4, column 2) and the testimony cannot be satisfied at all. So not there.
Put Lidia in Generator Room (row 6, column 1) and the testimony cannot be satisfied at all. So not there.

Show what goes wrong

Suppose Simon stood on the dashed square. Rita then has nowhere left to stand: every square still open to them is shaded out.

Another 9 squares fell the same way.

The answer

That leaves one arrangement, and one person who could have done it: Rita, in Airlock (row 4, column 5).

Show the solved board

The only arrangement the testimony allows. Rita is ringed in red.

Hard — The Bunker

A 9×8 grid across 7 rooms: Generator Room, Shelter, Watchtower, Airlock, Hydroponics, Pantry, Workroom. Fourteen statements, fourteen squares nobody could stand on, almost as many rooms as suspects, so a room claim nearly names a square, and one round of assume-and-test after elimination ran dry.

Cracked by 5 detectives so far.

How this case was cracked — the full solution to this board, step by step

Every step below is the solver’s own — the same one that proved this board has exactly one answer. The counts are real: you can check them against the grid.

Lettered squares are objects. Most take the square out of play — which is why the counts above are of free squares, not of all of them — but the ones marked below do not: their square is still in play. B — bed (square stays free) · CA — carpet (square stays free) · CO — computer · CR — crate · F — floor lamp · G — garbage can · P — potted plant · R — radio · S — stove · WD — wooden table · WO — wooden chair (square stays free)

The testimony

What each person said, and how much of the board it rules out.

Ofelia was in the same room as the Curator.
Wanda was exactly 4 columns east of Tesa.
Pablo was exactly 1 row south of Wanda.
Pablo was in the same column as the wooden table. leaves 7 of 61 squares
Show it on the board
The squares this one statement leaves Pablo: 7 of 61.
Pablo was somewhere south of the Curator.
Hugo was exactly 1 row south of Queralt.
Hugo was exactly 4 columns west of the Curator.
Hugo was somewhere south of Pablo.
Hugo was somewhere west of the Diva.
Tesa was somewhere west of Pablo.
Tesa was exactly 1 row south of the Curator.
Enzo was somewhere west of the Heiress.
Queralt was exactly 2 columns east of Tesa.
Queralt was all alone in a room.

Show the squares Pablo had left

The squares still open to Pablo once their own statements are taken into account — 7 of 61.

The squares that had to be tested

The rest does not fall out on its own. It takes 127 eliminations of the same move: put someone on a square, follow the consequences, and watch the board contradict itself.

Had Ofelia stood in Shelter (row 1, column 7), Tesa would have had nowhere left to stand. So not there.
Had Wanda stood in Shelter (row 1, column 6), Pablo would have had nowhere left to stand. So not there.
Had Pablo stood in Hydroponics (row 2, column 5), Wanda would have had nowhere left to stand. So not there.
Put Hugo in Airlock (row 3, column 2) and the testimony cannot be satisfied at all. So not there.

Show what goes wrong

Suppose Ofelia stood on the dashed square. Tesa then has nowhere left to stand: every square still open to them is shaded out.

Another 123 squares fell the same way.

The answer

That leaves one arrangement, and one person who could have done it: Hugo, in Watchtower (row 7, column 3).

Show the solved board

The only arrangement the testimony allows. Hugo is ringed in red.

Hard · time attack — The Bunker

A 9×8 grid across 7 rooms: Pantry, Generator Room, Radio Room, Dormitory, Shelter, Workroom, Watchtower. Thirteen statements, fifteen squares nobody could stand on, almost as many rooms as suspects, so a room claim nearly names a square, and one round of assume-and-test after elimination ran dry.

The twist: the accusation also demands the motive, not just the name.

Cracked by one detective so far.

How this case was cracked — the full solution to this board, step by step

Every step below is the solver’s own — the same one that proved this board has exactly one answer. The counts are real: you can check them against the grid.

Lettered squares are objects. Most take the square out of play — which is why the counts above are of free squares, not of all of them — but the ones marked below do not: their square is still in play. B — bed (square stays free) · CA — cabinet · CO — computer · CR — carpet (square stays free) · CT — crate · F — floor lamp · G — garbage can · P — potted plant · R — radio · S — stove · WD — wooden table · WO — wooden chair (square stays free)

The testimony

What each person said, and how much of the board it rules out.

Sofia was in the same room as Oscar.
Sofia was exactly 2 columns west of the Colonel.
Oscar was in the same room as the Diva.
Oscar was exactly 3 rows north of Petra.
Ximena was in the same row as the wooden table. leaves 6 of 60 squares
Show it on the board
The squares this one statement leaves Ximena: 6 of 60.
Ximena was in the same column as the carpet. leaves 1 of 60 squares
Show it on the board
The squares this one statement leaves Ximena: 1 of 60.
Irene was in the same column as the crate. leaves 5 of 60 squares
Show it on the board
The squares this one statement leaves Irene: 5 of 60.
Petra was somewhere south of Irene.
Elena was somewhere north of the Doctor.
Marco was somewhere north of the Doctor.
Marco was exactly 3 columns east of the Chef.
Marco was in the pantry or in the shelter. leaves 15 of 60 squares
Show it on the board
The squares this one statement leaves Marco: 15 of 60.
Marco was all alone in a room.

Show the squares Irene had left

The squares still open to Irene once their own statements are taken into account — 5 of 60.

The squares that had to be tested

The rest does not fall out on its own. It takes 91 eliminations of the same move: put someone on a square, follow the consequences, and watch the board contradict itself.

Had Sofia stood in Generator Room (row 1, column 2), Irene would have had nowhere left to stand. So not there.
Had Oscar stood in Generator Room (row 2, column 4), Sofia would have had nowhere left to stand. So not there.
Had Ruben stood in Generator Room (row 1, column 1), Elena would have had nowhere left to stand. So not there.
Put Irene in Generator Room (row 4, column 2) and the testimony cannot be satisfied at all. So not there.

Show what goes wrong

Suppose Sofia stood on the dashed square. Irene then has nowhere left to stand: every square still open to them is shaded out.

Another 87 squares fell the same way.

The motive

This case demands the why as well as the who: naming the killer without proving the motive counts for nothing. 7 motives are in play, and these statements narrow them.

Elena's motive would have been blackmail.
Oscar's motive would have been jealousy.
Sofia's motive would have been obsession.
Irene's motive would have been buried secrets.
Whoever did it was not driven by inheritance.
Whoever did it was not driven by ambition.

The answer

That leaves one arrangement, and one person who could have done it: Ximena, in Generator Room (row 3, column 3).

The only motive left standing for Ximena is debts.

Show the solved board

The only arrangement the testimony allows. Ximena is ringed in red.

Expert — The Bunker

A 10×9 grid across 7 rooms: Airlock, Radio Room, Shelter, Dormitory, Workroom, Watchtower, Generator Room. Fifteen statements, seventeen squares nobody could stand on, and two rounds of assume-and-test after elimination ran dry.

Cracked by 5 detectives so far.

How this case was cracked — the full solution to this board, step by step

Every step below is the solver’s own — the same one that proved this board has exactly one answer. The counts are real: you can check them against the grid.

Lettered squares are objects. Most take the square out of play — which is why the counts above are of free squares, not of all of them — but the ones marked below do not: their square is still in play. B — bed (square stays free) · CA — cabinet · CO — computer · CR — carpet (square stays free) · CT — crate · F — floor lamp · G — garbage can · P — potted plant · R — radio · S — stove · WD — wooden table · WO — wooden chair (square stays free)

The testimony

What each person said, and how much of the board it rules out.

Marina was somewhere west of the Doctor.
Marina was all alone in a room.
Marina was exactly 2 columns east of the Gardener.
Yolanda was in column 5. leaves 8 of 76 squares
Show it on the board
The squares this one statement leaves Yolanda: 8 of 76.
Victor was somewhere north of the Colonel.
Dorian was somewhere west of the Curator.
Dorian was exactly 2 rows south of the Doctor.
Zeno was all alone in a room.
Zeno was exactly 6 rows south of the Journalist.
Luna was all alone in a room.
Nico was somewhere east of Zeno.
Abel was exactly 6 columns west of the Journalist.
Abel was in the same row as the radio. leaves 8 of 76 squares
Show it on the board
The squares this one statement leaves Abel: 8 of 76.
Abel was all alone in a room.
Exactly 3 people were in the workroom.

Show the squares Yolanda had left

The squares still open to Yolanda once their own statements are taken into account — 8 of 76.

The squares that had to be tested

The rest does not fall out on its own. It takes 188 eliminations across 2 rounds of the same move: put someone on a square, follow the consequences, and watch the board contradict itself.

Had Marina stood in Generator Room (row 3, column 4), Sofia would have had nowhere left to stand. So not there.
Put Yolanda in Generator Room (row 2, column 5) and the testimony cannot be satisfied at all. So not there.
Had Sofia stood in Generator Room (row 2, column 3), Victor would have had nowhere left to stand. So not there.
Put Victor in Generator Room (row 2, column 3) and the testimony cannot be satisfied at all. So not there.

Show what goes wrong

Suppose Marina stood on the dashed square. Sofia then has nowhere left to stand: every square still open to them is shaded out.

Another 184 squares fell the same way.

Marina can only be in Radio Room (row 5, column 3) — down from 4 possible squares.
Yolanda can only be in Generator Room (row 4, column 5) — down from 2 possible squares.

The answer

That leaves one arrangement, and one person who could have done it: Yolanda, in Generator Room (row 4, column 5).

Show the solved board

The only arrangement the testimony allows. Yolanda is ringed in red.

Expert · time attack — The Bunker

A 10×9 grid across 7 rooms: Hydroponics, Shelter, Generator Room, Workroom, Airlock, Pantry, Dormitory. Twelve statements, eighteen squares nobody could stand on, and two rounds of assume-and-test after elimination ran dry.

Cracked by one detective so far.

How this case was cracked — the full solution to this board, step by step

Every step below is the solver’s own — the same one that proved this board has exactly one answer. The counts are real: you can check them against the grid.

Lettered squares are objects. Most take the square out of play — which is why the counts above are of free squares, not of all of them — but the ones marked below do not: their square is still in play. B — bed (square stays free) · CA — cabinet · CO — computer · CR — carpet (square stays free) · CT — crate · F — floor lamp · G — garbage can · P — potted plant · R — radio · S — stove · WD — wooden table · WO — wooden chair (square stays free)

The testimony

What each person said, and how much of the board it rules out.

Beatrix was in the same row as the bed. leaves 8 of 75 squares
Show it on the board
The squares this one statement leaves Beatrix: 8 of 75.
Petra was exactly 2 rows south of the Professor.
Elias and Marco were alone together in one room.
Elias was exactly 4 rows south of Abel.
Ofelia and Marco were in different rooms.
Abel was exactly 1 column west of the Professor.
Marco was exactly 7 columns east of the Doctor.
Victor was exactly 2 columns east of Sofia.
Sofia was exactly 1 column east of the Professor.
Exactly 2 people were in the workroom.
Exactly 3 people were in the pantry.
Exactly 2 people were in the generator room.

Show the squares Beatrix had left

The squares still open to Beatrix once their own statements are taken into account — 8 of 75.

The squares that had to be tested

The rest does not fall out on its own. It takes 267 eliminations across 2 rounds of the same move: put someone on a square, follow the consequences, and watch the board contradict itself.

Had Petra stood in Dormitory (row 3, column 2), Gilda would have had nowhere left to stand. So not there.
Had Elias stood in Airlock (row 6, column 6), Victor would have had nowhere left to stand. So not there.
Had Ofelia stood in Hydroponics (row 1, column 4), Marco would have had nowhere left to stand. So not there.
Had Abel stood in Hydroponics (row 1, column 4), Elias would have had nowhere left to stand. So not there.

Show what goes wrong

Suppose Petra stood on the dashed square. Gilda then has nowhere left to stand: every square still open to them is shaded out.

Another 263 squares fell the same way.

Beatrix can only be in Pantry (row 9, column 1) — down from 2 possible squares.
Petra can only be in Generator Room (row 7, column 9) — down from 5 possible squares.
Elias can only be in Workroom (row 6, column 7) — down from 6 possible squares.
Ofelia can only be in Pantry (row 5, column 3) — down from 3 possible squares.
Abel can only be in Hydroponics (row 2, column 2) — down from 3 possible squares.
Marco can only be in Workroom (row 8, column 8) — down from 3 possible squares.
Victor can only be in Shelter (row 1, column 6) — down from 3 possible squares.

The answer

That leaves one arrangement, and one person who could have done it: Petra, in Generator Room (row 7, column 9).

Show the solved board

The only arrangement the testimony allows. Petra is ringed in red.

How to read a case above

The grid size is the size of the crime scene, so a 10×9 expert case is a far larger search than a 5×5 beginner one — but the difficulty is really carried by the clues, not the square count. A beginner case tells you almost directly where somebody stood. An expert case tells you where somebody was not, three times, and expects you to do the rest — and on half of them one of those statements is a lie told to protect the killer. If a case lists a motive, naming the right person is not enough on its own; you have to prove why.

How to play · Solving cases with a liar · Techniques

The day in review

The Archivist’s Silence — The cache at The Bunker came up — found, marked, logged. Not the thing that went missing on day one, but something.

All ten investigations unfolded underground at The Bunker on the twenty-second of September. Standard inquiries drew modest company, beginning with twenty-three attempts on the 5x5 beginner layout, twenty of which reached a conclusion. The 6x6 easy grid saw seventeen investigators try their hand, all seventeen succeeding. Medium difficulty pushed the boundaries across an 8x7 floor plan, claiming twelve solutions from seventeen attempts, while the 9x8 hard board proved stubborn, yielding four solutions from nine plays. The 10x9 expert challenge was smaller still, though all four attempts cracked the seven rooms.

The time attack runs through the concrete halls saw thin crowds and little room for error. The 5x5 beginner case was solved six times in seven tries, the 6x6 easy assignment saw three successes from three, and the 8x7 medium room held two attempts, both solved. The 9x8 hard layout introduced the day's only motive requirement, where just one of two contenders prevailed. The solitary investigator to enter the 10x9 expert time attack managed to close the file cleanly.

A familiar name dominated the ledger. Chentian logged the fastest marks across nearly every case, recording 0m 11s on standard beginner, 0m 18s on standard easy, 0m 54s on standard medium, and 17m 32s on standard hard. Chentian swept the clock runs as well, posting 0m 09s on beginner, 0m 13s on easy, 0m 29s on medium, 8m 44s on the motive-heavy hard board, and 16m 35s on expert. Only the standard expert board eluded that grasp, where annemarie claimed the swiftest finish in 8m 48s.

Fastest detectives of the day

Beginner: chentian — 0m 11s · Easy: chentian — 0m 18s · Medium: chentian — 0m 54s · Hard: chentian — 17m 32s · Expert: annemarie — 8m 48s · Beginner · time attack: chentian — 0m 09s · Easy · time attack: chentian — 0m 13s · Medium · time attack: chentian — 0m 29s · Hard · time attack: chentian — 8m 44s · Expert · time attack: chentian — 16m 35s