Ghost House
Ghost Houses, listed in the Super Mario World manual as Haunted Houses, are large buildings where various Boos live. Since the player can save his or her game every time one of these houses is completed in Super Mario World, it is encouraged that Ghost Houses are returned to regularly as a way to save progress. There are six Ghost Houses in Dinosaur Land: two in Donut Plains, one inside the Vanilla Dome areas, one in the Forest of Illusion, one on Chocolate Island, and one in Valley of Bowser. As with Castles, Yoshi will stay outside of the Ghost House when Mario or Luigi enters. The given reason is Yoshi's fear of ghosts, but the technical reason is because the doors inside ghost houses (and castles) can't be entered while riding Yoshi.
Big Boo's Haunt of Super Mario 64 is a Ghost House, as is Boo's Mansion of Paper Mario. Additionally, Creepy Steeple in Paper Mario: The Thousand-Year Door is a Ghost House. And of course Luigi's Mansion from the game of the same name is a ghost house.
Level nine: Ghost Mansion in the game Yoshi's Safari is a Ghost House. The level is full of boos that Mario and Yoshi must shoot down with the super scope. Mario and Yoshi will eventually reach the end to face Big Boo the level's boss.
The only Ghost House of Super Mario Sunshine is Sirena Beach's Hotel Delfino. Several Ghost Houses are in New Super Mario Bros.; these introduced more new ghost species such as the Ghost Glove. The game also featured the exclusive Ghost House quirk of having Boos cover up the bottom screen while Mario or Luigi was inside a Ghost House. The Ghost Houses reappeared in New Super Mario Bros. Wii, this time with Boos flying around them, just like in Super Mario World.
During Dance Dance Revolution: Mario Mix a Ghost House is found in Wario's Carnival. Though this so-called "Ghost House" is actually a traditional false haunted house (as seen in several Real World carnivals), it actually contains Boos and the occasional Big Bubble.
