Revealing mistake: During the shot where Chuck flips Spencer for a brief second you can see his face, which reveals that it's a stuntman as he is a different person.
Revealing mistake: Carly, Sam and Shelby all corner Nevel in the ring. If you look in the corner where Shelby shows up, she's not in that corner until the light flashes on her.
Answer: In direction translation it means 'Mischievous Spirit'. 'Hob' as in HobGoblin means clown or prankster, and 'Knocker' was an old age term for Poltergeists in mines. Miners would often complain of hearing knocking sounds down mines when there was no-one else down there, hence 'Knocker'. It's not a regular English expression though.
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