A Cycloptopus is a one-eyed octopus-like creature.
In "Dungeons, Dungeons, and More Dungeons," a Cycloptopus is first seen wrapped around Ford's arm, attacking him as he enters the Mystery Shack gift shop. It then tries to escape and hisses at Dipper, Mabel, and Stan , but Ford quickly pursues it. After cornering the creature, Ford electrocutes it with his gloves, incapacitating it. Later in the episode, when Dipper falls into the underground laboratory, he accidentally releases the Cycloptopus and it latches on to Ford's face. Ford pulls it off, leaving suction marks.
The Cycloptopus has a green body and resembles an octopus, but instead of having two small eyes it has one large lime green eye which also serves as a mouth. The underside of its tentacles is a brighter shade of green and has suction cups which leave marks on skin.
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