Medium
Room counting
Count who can still be in a room: the victim needs exactly one companion.
Three clues are about how many people share a room. The victim's room holds exactly one other person. "With another man" means exactly one other man. "Alone" means nobody else.
Use them both ways. If the victim could only be in a room nobody else can reach, that room is out for the victim. If exactly one person can still reach the victim's room, they are the killer and they are in it. If a room already has its one companion, cross the room out for everyone else who is left.
The three counting clues
The victim's card is the first. The victim's room holds the victim and exactly one other person, so it never holds two others and never none. "He was in the Study with another man" says the Study holds him and exactly one other man; women may be there as well. "She was alone in the room" says nobody else stood in her room.
Finding the victim's room
Count the suspects who can still reach each room. A room no other suspect can reach is closed to the victim, because the killer has to be in there too. A room that will certainly hold two other people is closed for the same reason. When only one room fits, the victim is in it.
It works the other way too. Once you know the victim's room, count who can still reach it. If exactly one person can, that person is the killer and stands in the room. If one suspect is already placed there, the room is closed to everyone else who is left.
Using "alone"
A suspect who was alone needs a room nobody else uses. Any room with someone already placed in it is out for them, and once they are placed, their room is out for everyone else. "Alone" clues are common in Medium cases and often open up the middle of the board.
Counting clues need the whole board in view, so they usually come after the row and column techniques. Keep a short list of rooms with the people who can still reach each one, and update it after every placement.
Practice case: Medium 6×6
This case needs the technique above. Try it before you read the next tip.
He was beside a rug.
Pick a suspect, then tap a cell.
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