Magic Window

Magic Window is a secret Attack Piece used in Mario & Luigi: Bowser's Inside Story.

When using this special technique, Mario and Luigi jump into a window, which teleports them close to a random opponent. As Mario or Luigi jump out of window, the player has to decide which button to press: A, B, or both of them. This attack will cost eighteen SP to use.

This is unlocked by defeating the optional Shroob boss.