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Karl (w/a K) is a mutant green lantern fish-like monster that disguises himself into a human, like his twin brother Carl w/a C that first appear in Scared Silly.


Human form

Karl is a grown man with long grey hair, a closed eye that doesn't open, wears a brown suit and tie, and carries a three candleholder.

Monster Form

His true form has the appearance of a humanoid lantern fish. He is primarily a swampy green with blue dots scattered across his body, and like his human form, he also closes one of his eyes.


He seems friendly, if a bit creepy at first, but proves to be a malicious sadist later, cracking dark jokes about the situation of his enemies.


After dabbing in dark magic, Karl ended up turning into a monster and Carl into a ghost. Afterwards, it is implied that he started eating those who visited his hotel, to the point his brother tried to scare off those who tried to visit the hotel.

However, this ended during the events of Scared Silly. When Ben, Gwen, and Max ignored Carl's warnings, he invited them inside. After the trio trapped Carl, he revealed himself and tried to eat them. However, with the help of Carl, they managed to defeat him and he ended up, alongside his brother, getting sucked into a portal, presumably to the afterlife.

Powers and Abilities

Karl has some form of shapeshifting, changing between a human disguise and his true monstrous form. He also has the ability to use telekinesis and fire energy bolts from his lure.

Karl, in his monster form, has enough strength to toss Wildvine with great ease.


If his orb is destroyed, Karl will be defeated and get taken to, presumably, the afterlife.

Karl can be contained within Wildvine's vine.


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Season 4

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