Mystery Train
- “Ee hee hee hee... Good thing those Red Boos are gone! Now we can start the Mystery Train! Next stop, the Boneyard! To the Boneyard!”
- —Boo, Mario Party 4
The Mystery Train is a vehicle found in Mario Party 4. It is featured in an event on the board Boo's Haunted Bash. The Mystery Train is composed of four ghostly coffins that shimmer in a translucent blue and hover above the ground. It can be found in a cemetery-like environment in the northwestern corner of the board and is managed by a Boo. The event is triggered automatically once a player passes by.
The Mystery Train event is affected by the presence of the Red Boos on the board. The player gets a chance to ride the train if the Red Boos are absent while the event is triggered. The player then gets on one of the four coffins and hovers along the field. Any opponent that the train meets during its way gets picked up and rides the train as well. The player in the lead can decide in which direction the train moves until it reaches a graveyard where the players are released again. The player who started the event continues to move forward, depending on the number of steps they have left.
If the event is triggered while the Red Boos are present on the board, the Mystery Train does not depart. The Boo in charge appears and dismisses the player, claiming that the Red Boos are spoilsports and that the train does not move until they have vanished again.
