YMMV / Merlin S 02 E 01 The Curse Of Cornelius Sigan

• Complete Monster: Cornelius Sigan was the most powerful sorcerer in history and managed to discover the secret to immortality, by sealing his soul inside a jewel that was kept in his tomb. After his tomb is robbed by a thief named Cedric, who removes the jewel, Sigan's spirit possesses Cedric's body and with it intends to destroy Camelot. Sigan casts a spell that animates all of the gargoyle statues around Camelot and instructs them to slaughter everyone in Camelot. When discovering Merlin is also a sorcerer, Sigan offers to let Merlin join him, and upon Merlin refusing, Sigan tries to steal Merlin's body for himself.
• Jerkass Woobie: Cedric's a thief and a master manipulator, but there's no sign that he actually wants to harm Merlin or Arthur - he just wants the former out of the way so he can steal the latter's keys, and all he does is trick Arthur into sending Merlin away for a night. He probably didn't deserve to be possessed to death.

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