Secret Altar

The Secret Altar (Japanese: 秘密の祭壇 Secret Altar) is the final room in Luigi's Mansion. It is found in Area Four and is where the game's final boss, King Boo, resides. After Luigi retrieves the spade key in The Artist's Studio, he accesses the Secret Altar and defeats King Boo.

Description
The Secret Altar contains three chandeliers, one of which holds a Blue Stone. On the west wall is a stone lion's head on the other side of which is the Bottom of the Well (which is where the player first sees the room). On the east wall is a mirror flanked by two torches burning with incense. If Luigi vacuums the incense, one torch gives him money, and one torch gives him a gold bar. Two similar torches are found at the rear of the room on either side of Mario's painting. These and the two chandeliers near King Boo can be vacuumed, but they do not yield anything.

Trivia

 * The hallway to the altar appears straight on the map, but it actually zig-zags in game, there is little explanation why this is, and this is the only map in the game that does this.
 * If the first-person mode on the Game Boy Horror is used in the Bottom of the Well to scan the mirror, it will warp Luigi to the Foyer as usual, but with a couple of minor visual and audio glitches occurring.
 * When Luigi goes into the Secret Altar, he sees Mario trapped in a painting. Mario is wearing both his gloves and hat, even though Luigi collected them earlier.
 * During the blackout, if the player views the Secret Altar from the outside, the cutscene will play again, but there will be no dialogue and King Boo will be absent. Also, the lights will be off.