From the Super Mario Wiki
The Plunder Chest is Princess Peach's favorite item in Mario Party 2 and Mario Party 3. It is a treasure chest that can steal an item from another player.
In Mario Party 2, when used the Plunder Chest randomly chooses another player that is holding an item, steals their items and gives them to the player. In Mario Party 3, players can choose who they want to steal from, however if the person being targeted has two or three items, the item that is stolen is picked at random.
There is a much rarer version of the Plunder Chest in Mario Party 3, called the Barter Box, which swaps all of the player's items with all of the targeted player's items.
Name in Other Languages
Yo ko dori bokkusu
|Booty Coffer (Mario Party 2)|
Looting Coffer ('Mario Party 3)