Easter egg: On the 2-disc Special Edition, on Disc One, go to the Special Features menu and select Main Menu, then hit down. This highlights a previously unseen shape (cat food maybe?) that leads to a selection of Official "Overheard at the Monitor" Quotes from Guillermo del Toro.
Easter egg: On the widescreen DVD set, on the second disk, go to the Bellamie Hospital page. When you get there, hit the down arrow twice and you will be led to a hidden link located around halfway between the Final Campaign link and the Main Page link. Hit this to see a hidden drawing of the cast.
Easter egg: In the Region 2 DVD, press 'left' when in the main menu until it highlights a previously unseen shape. Select this to see the Director apologising for the Introduction he does for the DVD, and holding up and criticizing the cue cards he had been given to read for it. It's very funny.
Answer: The internal machinery that powers him is clockwork. It needs to be wound like a watch every so often. He releases most of the tension when he fakes his death.
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