Arcade (Mario & Luigi: Paper Jam)
From the Super Mario Wiki
The Arcade is a minigame area in Mario & Luigi: Paper Jam. It is located in the clouds above any Lakitu Info Center in the game, and it is accessible via a green pipe to the left of the entrance. Similarly to the Challenge Node from Mario & Luigi: Bowser's Inside Story, it hosts two extra modes: the Battle Ring and the Attackathon. The Bros. can also buy Lakitea for 20 coins from the nearby shopkeeper, which will fully heal all members of the party. The Arcade can only be accessed after going to Sunbeam Plains for the second time.