Reading the rules of a deduction game takes two minutes; learning to see the deductions takes a little longer. The tutorial is where the second part happens. It is two short cases on a real board, with the reasoning spelled out move by move as you make it — not a video, not a wall of text, and not a demo you watch. You place the suspects yourself and the game explains why each step follows.
The opening walkthrough is deliberately small, so that nothing on the board is hidden from you. It covers the mechanics: how to read a witness statement, how to mark a cell that somebody cannot occupy, and how to place a person once only one cell is left for them. The single most important habit in this game is crossing out rather than placing, and it is the habit the first case drills.
It also introduces the rule that does most of the work: every person, the victim included, stands in their own row and their own column. Place one person and an entire row and an entire column clear for everybody else. New solvers tend to treat each statement in isolation; the first case shows what happens when you let a placement cascade.
The second walkthrough moves from mechanics to reasoning. It introduces the rooms — a floor plan divided into named spaces, with statements that talk about rooms rather than about cells — and the second rule of the game: the room holding the victim contains exactly one suspect, and that suspect is your murderer.
That rule is far sharper than it first looks. A room known to hold the victim can take exactly two people, which constrains everybody who is not in it just as much as the person who is. The second case walks you through the first deduction that uses it, and through the combination step that most people miss: the opening move in a real case is usually two statements read together, not either of them alone.
There is one consequence of the row-and-column rule that almost nobody spots on their own, and it is worth arriving at with a board in front of you. Since no two people share a row, and no two share a column, two people can never be directly above, below, left or right of one another. The only adjacency this game permits is diagonal. A statement that two suspects stood beside each other is therefore enormously more informative here than the same sentence would be in any other grid puzzle — and a statement that they did not is a real constraint too.
It assumes nothing. You do not need to have solved a Sudoku, a nonogram or a logic grid before, and nothing in it depends on arithmetic — there is no counting, no addition and no arithmetic trick anywhere in this game. What it does assume is that you would rather be shown a deduction than told a rule, which is why it runs on a board you are playing rather than in a page you are reading.
It is also worth ten minutes to solvers who already know grid puzzles, because the constraint here is unusual. Most grid puzzles fill cells; this one places a fixed cast of people under a rule that forbids sharing a line. That single difference changes which observations are worth making, and the tutorial is the quickest way to retrain the instinct.
Every case on this site, the tutorial cases included, is verified before it is published: exhaustively checked to have exactly one valid arrangement, and then solved again by an engine that reasons strictly forward, one justified step at a time, with no trial and error anywhere. If a case is accepted, a human can reach the end by reasoning alone. When you are stuck, the next step exists. The tutorial is largely about learning to trust that.
The walkthrough takes about ten minutes and there is nothing to save and nothing to sign up for. When you finish, the easy cases in the casebook are the natural next stop — they are built to the same standards, only wider — and the difficulty ratings are honest about how much of the board stays open before the first person can be placed.