Jellybobs, originally known as Pneumos, are floating jellyfish found in Wario Land 3. A single Jellybob is featured as an opponent in Dr. Mario 64.
In Wario Land 3, Pneumos float in the air peacefully, until Wario appears; their horn-like nose transforms into a sting that turns Wario into Puffy Wario. They act very similar to the Bees found in Wario Land II.
In Dr. Mario 64, a single Pneumo, now renamed Jellybob, is in the ocean resting peacefully until he is angered and attacks Dr. Mario/Wario while they pursue the Megavitamins.
- ^ Official American Wario Land 3 website (Internet Archive)