The Guard Hall is a room in Gloomy Manor in the game Luigi's Mansion: Dark Moon. It is notable for having four Suits of Armor that attempt to attack Luigi by swinging their sword down. The Guard Hall also is accessible from the Entrance and it leads to the Foyer.
During the first mission of Gloomy Manor, Luigi heads down the Guard Hall where he has to avoid the Suits of Armor to get into the Foyer.
In a later mission, the Suits of Armor actually disappear from the Guard Hall but they will reappear later.