The first column is the four house names. Enter G, H, R, or S. These are not adjacent to anyone nor do they share diagonals with anyone. Each row only contains members of one house. CHARACTERS CAN BE IN ANY HOUSE. Moody and Dumbledore are considered professors; Crouch Jr is not in the quiz. A "student" is someone who attended Hogwarts during any year(s) Harry attended. Anyone mentioned is in the quiz. HP knowledge is required. Adjacent includes diagonally. Walkthrough is in the source.