Plunder Ground is a Free-for-All minigame in Mario Party 9.
Opening[]
There is a view of the four characters, who are on a tiny island, each facing one of the four treasure chests. At first, the view is briefly shown at an angle before slowly zooming in and centering on the characters from behind.
Gameplay[]

Monty Moles digging around underground
There are three rounds, and at the start of each one, there are four Monty Moles, each holding a chest. Jewels then fall into every treasure chest except for at least one. The treasure chests then close, and the Monty Moles then burrow with them underground, scrambling themselves around. During this, the players have to keep an eye on the Monty Moles, especially the one with the treasure chest containing the most jewels.
In the first round, three chests are filled with 10 jewels whilst one has no jewels. In the second round, two chests are filled with 15 jewels whilst two have none. In the third round, one of the chests is filled with 10 jewels, another is filled with 20, and the other two have no jewels. For each round, the Monty Moles move faster than in the previous one. Whoever ends the minigame with the most jewels is the winner.

The minigame in Perspective Mode
Plunder Ground also appears in Perspective Mode. Here, the camera is zoomed in on the player, making it harder to keep track of the Monty Moles.
Controls[]
: Move character
: Select a chest
Flavor text[]
- Rules: Watch the jewels fall into the chests, and then track the Monty Moles as they burrow. Try to pick a chest with jewels in it. The player with the most jewels after three rounds wins!
- Controls: Hold the Wii Remote sideways. Press
to move. Press
when standing in front of a chest to select it.
Trivia[]
- The minigame's name can be interpreted as either a pun on "underground" or a portmanteau of "underground" and "plunder."