The Bros. Ball is a move learned by Mario and Luigi in Mario & Luigi: Partners in Time. It is learned after the player returns to Princess Peach's Castle after the defeat of Sunnycide inside Yoob. The move makes a return in Mario & Luigi: Brothership.
Description[]
The move is taught to them by Toadsworth and Toadsworth the Younger in an attempt to calm down Baby Peach in Princess Peach's Castle. The move requires the Bros. to combine together in such a position where they resemble a ball. In their combined state, the Bros. look like a beach ball, with white spots on each side and sections in red, blue, green, and brown. The Bros. Ball allows them to move faster, enter passages once inaccessible, and hit certain switches. Another one of its functions is to flatten Baby Mario and Baby Luigi, allowing them to bypass walls as long as there is a very small gap.
Mario & Luigi: Dream Team introduces the Ball Hop, which seems to be an offshoot of the Bros. Ball used to jump up drops that cannot be surmounted with a regular jump.
The move returns in Mario & Luigi: Brothership, where the Bros. learn it on Lottacoins Island and need an escape route. It can now brake and move slowly. The move later receives an upgrade called the Ball Blitz. This is executed by holding X while using the Bros. Ball, and ten releasing the button. This done, the ball dashes quickly. This can be used to climb slopes that cannot be climbed easily and is learned in Slippenglide Island where the Bros. are stopped from reaching the lighthouse. Additionally, the Bros. and their copies merge into a giant wheel that seems to be a bigger version of the Bros. Ball and rips through all enemies in combat in the new version of the Yoo Who Cannon used in this game.