Uil is the evil version of Luigi, sporting a gray shirt & hat, with black overalls. He is the 'brother' of Ram, and is pure evil. He was manifested, along with Ram, when Fawful exploded at the end of Mario & Luigi: Bowser's Inside Story. The darkness released by the explosion latched onto the nearest lifeforms, Mario and Luigi, and copied their form, much like the Dark Star did with Bowser.
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