There are some aliens which are captured during the episode of Around the Universe in 80 Days. They are Plesiosaur, Joker, Irisben, Emperben, Thundersaurus, and many others.
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Joker is a Clian from Planet Thalios. Joker can make psychic connections between many people, but it is mute. Joker looks funny and make even a sadistic person to laugh! Joker's weakness is that he cannot talk or see a person if a object is covering it. He can be killed by deadly chemicals.
Plesiosaur is a Thallasauran from planet Aquarios. It can freeze enemies with its horns. Plesiosaur feeds on wood from its planet. It is a long necked, iguana-like alien. Aquarios was described by Ben as the home of aquatians.