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Bros. Items are special items used by Mario, Luigi, Baby Mario, and Baby Luigi in Mario & Luigi: Partners in Time. Bros. Items are different from regular items in that they are used for attacking one or multiple enemies at once (oftentimes with a specialized jump attack), and depending on the item, they require at least two characters or all four characters to be active in battle when utilized. Bros. Items are introduced by Toadsworth the Younger in Hollijolli Village when Baby Mario and Baby Luigi fight the three Shroobs in the village, with the Green Shell item, and later on the player obtains different kinds of Bros. Items, either from ? Blocks or buying them from item shops.
Bros. Items replace Bros. Attacks from Mario & Luigi: Superstar Saga, though they are replaced by the very same attacks in Mario & Luigi: Bowser's Inside Story (being named "Special Attacks" in that game), and in all subsequent Mario & Luigi games (Mario & Luigi: Dream Team, Mario & Luigi: Paper Jam, Mario & Luigi: Superstar Saga + Bowser's Minions and Mario & Luigi: Bowser's Inside Story + Bowser Jr.'s Journey).
List of Bros. Items
The table below shows the Bros. Items available in the game, along with the number of bros. required to use each of them: