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Bean Fever is a condition endemic to the Beanbean Kingdom. It causes whoever has it to gradually turn into a Bean in three days. Bean Fever can only be contracted by foreigners. It is caused by the consumption of unfamiliar beanish food, one known food being the Invincishroom, or rather in the remake, what was thought to be the "Invincibility Mushroom" yet was actually a Poison Mushroom. Mario acquired this disease while in Little Fungitown during Mario & Luigi: Superstar Saga, prompting Luigi to go on a solo mission to find the cure, which happens to be Crabbie Grass. Unfortunately, Mario's bedridden state and Luigi's absence allows Cackletta, now revived as Bowletta after possessing Bowser, to abduct Princess Peach to restart her evil plans.
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