King Boo's Haunted Hideaway is a large haunted house located in the middle of an old forest. The mansion itself seems to deviated from Luigi's Mansion and Horror Land from Mario Party 2. The unique thing about this board is that it has no set path. Every time the board is played, a different path is created out of preset "track pieces" making the mansion into an impossible maze. The goal of the maze is to find the mansion's owner, King Boo, who will trade a star for ten coins. King Boo however, only appears at one of the three (or sometimes two) ends of the maze, the other(s) lead to large holes, called pitfalls. If a player makes it one of these rooms, they are confronted by a swarm of Pink Boos, who send them back to start.
In Duel mode, the winning conditions were to get 2 Stars by finding King Boo twice with 10 coins each time (a little like Neon Heights from Mario Party 7). Here, the mansion stayed the same, and areas that were revealed stayed that way even when players went back to start after finding King Boo.
- Duel and Challenge Spaces are added, and Lucky Spaces removed.
- The mansion has twice as many rooms (24 instead of 12 for a standard four-player game) and there are three King Boo rooms where players can buy a star.
- The ? Spaces in front of Piranha Plants will make the flowers chew on players for 10 coins. ? Spaces next to mirror cabinets will transport another player to the space, determined by a dart wheel. The ? Space next to Mowz will let the player steal something from another player via a large pinball game. ? Spaces next to shaking chests will open the chest, giving the player a random piece of candy, 20 coins, or Pink Boos that swipe 10 coins away from the player.
Upon activating the Lucky Space, The player ascends a set of stairs into a large secret attic lined with coins and old chests. At the very end, there is a pipe that transports the player to King Boo's room. Then, the original rules apply
DK and Bowser Spaces
If Donkey Kong's space is activated, he will plug up all pitfalls and give the first player to reach him a free star, but if Bowser's Space is activated, then the first player who reaches him must give up a star. If they have no stars, Bowser will give them 10 coins.