Four frenemies are spending a long weekend together in an old Victorian house. They are Dr. Ruby, Prof. Gold, Mr. Green, and Ms. Sapphire. Their vacation takes place over four days: Thursday through Sunday. The house contains four rooms where they may encounter each other: the drawing room, the kitchen, the library, and the parlor.
Unfortunately, all four occupants of the house are both homicidal and suicidal. Each of them wishes all the others dead, and also wants to end their own life. There are four weapons available to them: an axe, a gun, a knife, and poison. On each day during their stay, each of them will attempt to kill either themselves or another person, using one of these weapons. Fortunately, they are incompetent, and all of these attempts will fail.
To solve this puzzle, determine a way that on each day, in each room, each person attempts to end one life with a certain weapon. Each day, in each room, there is a different killer, a different victim, and a different weapon used. Neither the killer, victim, nor weapon are repeated in the same room, nor on the same day. There are also no repeats between killers and weapons, killers and victims, or weapons and victims.
For each day, in each room, name the killer, the victim, and the weapon. There is more than one possible solution. You can use the grid above to work out your answer. Each square in the grid will have a killer, a weapon, and a victim. In the case of suicide, the killer and victim will be the same color. Drag the killers, weapons, and victims into the grid to see if you can find a way where no elements repeat for any day or room, and there are no repeats between killers and weapons, killers and victims, or weapons and victims. (To use the grid on mobile, press the full screen button and turn your device horizontal.)
This puzzle is based on a Graeco-Latin square.
Solution?