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The Koopa Cruiser is Bowser's personal airship. It was used in Mario & Luigi: Superstar Saga to transport Mario, Luigi, and Bowser to the Beanbean Kingdom while the Mario Bros. and Bowser were temporarily working together. After the battle against Fawful, the Koopa Cruiser crashed down to Stardust Fields. The Cruiser (in a poorly-repaired form) was later used by Bowletta to capture Princess Peach, who turned out to be Luigi in disguise, although their attempt at doing so was unsuccessful as Luigi, stalling them with help from the Koopa Cruiser's Pinch Crane, managed to not only escape but also return the Beanstar to Beanbean Castle. It is unknown what happened to the Koopa Cruiser after the events of the game - it is likely it returned in Bowser's possession.
Another Koopa Cruiser appeared in Mario & Luigi: Partners in Time to evacuate Baby Bowser, Baby Mario, Baby Luigi, Baby Peach and the young Toadsworth from Peach's Castle after it was attacked by Shroob UFOs. The Shroob UFOs attacked the Cruiser, forcing it to drop altitude over Hollijolli Village. Baby Bowser is coaxed into into rescuing Mario and Luigi from the Shroobs and the Bros. are brought aboard. As the Cruiser flies over Peach's Castle, which had been captured by the Shroobs and was then called Shroob Castle, Princess Shroob launched a Shroob Missile that shot down the Cruiser sending it crashing into Bowser's Castle.
The Koopa Cruiser also appears in Mario & Luigi: Superstar Saga + Bowser's Minions, with the same role as in the original game. It also appears in Minion Quest: The Search for Bowser, where it crashes and separates Bowser's minions at the beginning of the mode. After the Teehee Valley missions are completed, the Lakitu finds the Koopa Cruiser in Joke's End. It is found in the mission Gather the Cruiser Parts!, where it is found in ruins, causing the minions to search the area for replacement parts. It is repaired in the mission Return of the Koopa Cruiser, though Roy Koopa battles the minions after it is fixed. In The Trio's Last Stand, Private Goomp, Corporal Paraplonk, and Sergeant Guy place a bomb on the Koopa Cruiser, and they must be defeated to deactivate it. The minions then use the Koopa Cruiser to reach Bowser's Castle.
Oddly, in Mario & Luigi: Superstar Saga, Bowser said the Koopa Cruiser was his new weapon, but he had used a version of it in the past. Another thing that doesn't add up is when the Koopa Cruiser crashed into Stardust Fields one of the Koopas will say that they hadn't finished paying it off; though it's possible that this was an entirely different Koopa Cruiser, considering the one Baby Bowser had owned crashed into his castle in the past and was never repaired. Bowser refers to his ship's Koopa crew as Bowser Baddies.
Mario & Luigi: Superstar Saga
Bordering or connecting locations to the Koopa Cruiser in sequence:
Mario & Luigi: Superstar Saga
Mario & Luigi: Partners in Time
Names in other languages