What is a murdoku?
A murder puzzle on a grid. You get a floor plan, a body, and one card per suspect saying what that person saw. Exactly one arrangement follows from them, and so exactly one murderer.
The rules
- The board is a square grid, carved into named areas.
- Everyone stands on their own square: one person per row and one per column. No two people ever share a row or a column.
- The victim counts and has a square of their own. With five suspects the grid is six by six.
- Where the victim was is not given. You deduce it like everyone else: the victim’s card only says they were alone with the murderer.
- Some squares hold furniture. You can sit on a chair or a couch; nobody stands on a table or a cupboard.
- “Beside” means the next square along (above, below, left or right) and in the same area. Diagonals do not count, and through a wall does not count.
- The murderer is whoever was alone with the victim in the same area.
The kinds of clue
Four kinds, and no more. That is why a murdoku takes two minutes to explain to a class.
Which area
Where somebody was, or was not.
“They were not in the canteen.”
Which thing
What somebody was on, or beside.
“They were sitting in a chair.”
Beside whom
Who stood next to whom, in the same area.
“They were beside Youssef.”
Which way
Who was further up, down, left or right.
“They were further left than Elin.”
How to solve one
By ruling out. Every clue removes squares; what is left is the answer.
- Read every card before writing anything down. Together they pin more than any of them does alone.
- Start with what a clue rules out: “was not in the kitchen” removes a whole area in one go.
- Then rule out along rows and columns. The moment somebody is placed, that row and that column are closed to everyone else.
- Watch the furniture. Whoever sat on a chair is on a square with a chair, and there are usually only a few.
- Last, see who is left alone with the body. That is your murderer.
Where the word comes from
Murdoku is “murder” plus “sudoku”: a murder, solved the way you solve a sudoku. The grid with one person per row and column comes from the sudoku; the areas and the clue cards come from the murder game. The idea is not ours. We make the tool you write your own with.
Whose it is
Murdoku was created by Manuel Garand, a puzzle designer from Montreal. His puzzles are at murdoku.com, a new one every week and free, and in the book Murdoku: 80 Murder Mystery Logic Puzzles. If you want good puzzles to play, start there. If you want to make one with your own class in it, you are in the right place.
Go to murdoku.comMaking your own murdoku
There is no shortage of places to play one. What there is not, is a place to make one with the names of your class, the rooms of your school and the furniture that is really in them. That is what this is for. You pick the people, draw the floor, lay the body down, and the clues are written and checked: one solution, always.