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Why a Deduction Case Works on a Night Like This
Because it does the three things you need when you have people over and nobody wants to read a rulebook.
It takes five minutes to explain. One person per row and per column, the cards tell the truth, and whoever ends up in the victim's area is the murderer. That is it.
Everyone starts at the same time. No turns, no dice, nobody waiting on anybody. Whoever shows up late sits down and plays.
It ends. A case lasts about as long as a conversation, has exactly one solution and can be checked. Nobody is left feeling the game dragged on by itself.
And on top of that, the theme fits the night: there is a body, and someone has to be named.
What You Need, and What You Don't
You need a printer, pencils and a table. Nothing else.
Under printable cases there are free cases, no sign-up needed. Each one comes in color, in black and white — the one you want if you are printing eight copies, because it goes easy on the ink — and with the solution as a separate PDF, which is exactly what you want with people around: you hand it out at the end.
You do not need costumes, an app or anything prepared the day before. And if you have no printer, you can play in the browser, passing a phone or tablet around, although in a group paper wins: everyone crosses out on their own sheet.
The Format That Works Best: A Detective Race
Print the same case for everyone and hand it out. Pairs work better than playing solo: the fun is in hearing people argue.
One rule changes everything: you do not win by naming the murderer, you win by proving it. When you raise your hand, you have to explain the first step — which card you tackled first and why that one — and if it does not hold up, the race goes on. Without that rule, someone guesses right in three minutes and the night is over.
When only one pair is left, give them the solution and have them read it out loud: it comes with the reasoning written alongside, not just the finished map. That is when someone says “Oh, of course!” and asks for another one.
Three Variations, Depending on the Group
Teams, out of earshot. Two teams in different rooms with the same case. The first one back with the name and the reason wins. It gets loud.
Around the table. One case in the middle of the table and one-minute turns: each person crosses out one square and explains why. It goes slowly and everyone follows along, which is what you need if there are kids.
From easy to hard. Start with a small case so the rules sink in as you play, then bring out a big one for anyone who wants to stay. The ones who get tired head to the kitchen, and the ones who stick around have their night sorted.
The Settings That Set the Mood
This year there are Halloween cases, three of them: they take place in a haunted mansion, with the suspects in costume, and you will find them among the printable cases.
All six Halloween cases, the haunted mansion and Trick or Treat, are together in printable Halloween logic puzzles.
Even so, you do not need pumpkins for a case to carry the night. What sets the mood is the place: a mansion, with its hallways and parlors; a forest; a museum at night, after closing time; a swamp; a cave; a night train.
It is exactly the backdrop of a classic mystery novel, which is what that night calls for. And since every case comes with its own illustrated map, you can leave it on the table as part of the decorations.
With Kids, and With Adults Who Play Like Kids
With kids, pick a small case with few suspects: it takes a few minutes and everyone can read the step-by-step together. And before you start, explain what “next to” means — on the neighboring square and in the same area; walls break it — because it is the only rule people misread.
With adults, the problem is the opposite: someone will try to solve it in their head without crossing anything out, get stuck and declare that the case is broken. Keep pencils handy and make them cross things out. You solve it by ruling things out, not by guessing.
And If Someone Likes It a Little Too Much: The Book
There is always one person who asks, at the end of the night, where to find more. The answer is Sudoku Detective: a paperback, in full color, with illustrated settings and the solution to every case explained step by step. It is the kind of gift that actually gets used, and it works for Halloween as well as for Christmas, which is right around the corner.
The cases in the book are only in the book, not on the website. In the meantime, the website is free, with new cases every week, and the full rules are here with a case solved from start to finish, in case you want to read them before anyone arrives.
Frequently Asked Questions
How many people do you need?
Anything from one person to a full table. For the race format, two to five pairs with the same printed case works best.
How long does it take?
A small case takes a few minutes, and a big one can take a good half hour or more. Two or three cases of increasing difficulty will fill the evening.
Do I have to print in color?
No. Every case also comes in black and white, designed precisely for printing several copies without using up your ink. The solution comes as a separate PDF.
Are there Halloween-themed cases?
Yes, three, and they are for printing: they take place in a haunted mansion, with the suspects in costume. You will find them on the printable cases page. The game on the website has no Halloween cases, but it does have settings with that same mood: a mansion, a forest, a museum at night, a swamp, a cave or a night train.
Can you play without a printer?
Yes, in the browser, with nothing to install and no account. In a group, though, paper works better: everyone crosses out on their own sheet.
Does it work for a class the day before Halloween?
Yes, and the cases are free to print and hand out in classrooms, libraries and nursing homes; all we ask is that you keep the credit: sudokudetective.com
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