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Jellybeams are a type of jellyfish enemies that appear in New Super Mario Bros. Wii. Their name is a pun on jelly bean, or a portmanteau of 'jellyfish' and 'beam'. They are only found in World 8-4 and serve to illuminate the dark waters. They are found along with Stone Spikes, Cheep-Cheeps, Deep-Cheeps, Bloopers, and Bulbers.
Despite helping Mario to see underwater, they can also hurt him if Mario touches them. Jellybeams can be defeated with fireballs or a Starman. Mario can also freeze them, causing them to stop moving, but they will continue to illuminate the water. Their movements can be compared to a Thwomp, although rather than slamming down on the ground when Mario approaches, automatically moves up and down slowly.
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