Triskaidekaphobia (Shadows over Innistrad) has many references to the number 13.
• 13 nails on the barrel
• 13 logs in the fireplace
• 13 large stones on the front of the fireplace
• 13 small stones on the arch of the fireplace
• 13 pieces of plate on the ground
• 13 streaks of blood on the walls
• 13 wooden planks forming the walls of the house
• 13 cooking tools hanging from the ceiling
• 13 beams on the ceiling