The minigame takes place between the ocean, and the skies filled with clouds. Four players are positioned in the ocean. There is a ship above the water, waiting for the players to retrieve Treasure Chests; while in the ocean, there are inhabitants that include a Sushi, a pair of Bloopers, fish, and coral. The minigame then starts.
The objective of the minigame is that the players will have the opportunity to grab treasure chests from the bottom of the ocean and retrieve them to the top to earn Coins within the time limit of ninety seconds. Treasure chests vary by size, weight and where it was placed. Small treasure chests contain only a single Coin, medium chests contain three Coins, and large chests contain five Coins.
To make the minigame harder, there are a pair of Bloopers that move within the water diagonally, and a Sushi that swims horizontally. If a player touches one of the enemies, the player will be stunned for a few seconds; additionally, if the player touches them while holding a treasure chest, they will be forced to drop the object back to the ground. Players have a limited time staying underwater, if they stay too long, a counter appears on top of their head, starting with number five. If it counts down to zero, they will drown and float back to the surface. There is no winner or loser.
The minigame can be purchased from the Mini-Game House for 250 Coins.
- Stick - Move
- A - Swim
- Game Rules - "Dive into the sea and bring up the Treasure Chests from the bottom. Press A to dive."
- Advice - "You'll start to drown if you are underwater too long. Come back to the surface for a breath once in a while."