Bowser Jr. Playroom

The Bowser Jr. Playroom (also known simply as Bowser Jr.'s Room in other regions) is a baseball field in Mario Super Sluggers. If the player chooses nighttime settings, the field turns into Bowser Castle.

The layout is the same as the Bowser Castle stadium of Mario Superstar Baseball. The walls of the field are very high, which makes it difficult to get home runs, and they have toys like Thwomps (which can break when hit) sitting on them. A giant Bowser Jr. statue also hangs over the middle of the wall and the whole field is surrounded in a train track and building blocks. In the outfield, there are many floor images of Chain Chomps and Bullet Bills. A Chain Chomp or Bullet Bill will pop up if its image was hit by the ball. The Chain Chomps and Bullet Bills will chase the player; the Chain Chomps run on the ground and the Bullet Bills fly. No matter what hit the player, they are stunned and drop or miss the ball. However, the enemies can be avoided if the player runs away fast enough. The field is colorful and has many toys for Bowser Jr. to play with.

The minigame played here is "Graffiti Runner".