Tyler is still a human being in this scene. But a few hours later, the by would be turned into a werewolf. Look out, Mystic Falls!
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The men are ready to take down Katherine on the episode "Masquerade." They look ready for battle, don't they?
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Don't be fooled, folks. Stefan isn't dancing with Elena here. That's Katherine.
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What could be on the minds of Stefan and Damon here? Our best guess: the death of Katherine.
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Damon does not look at all pleased with Bonnie in this photo, does he? We wonder if these two will ever hook up.
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Katherine attends a Masquerade Ball with Stefan on the aptly-titled episode "Masquerade." She seems to be taunting the vampire in this scene.
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Look at Damon in the background of this scene. He sure looks suspicious, doesn't he?
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Katherine is on the prowl on the episode "Masquerade." Most people at the party think she's Elena.
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The Vampire Diaries Season 2 Episode 7 Quotes

You aren't gonna kill Katherine... I am.

Stefan

Tell Damon and Stefan to give me the moonstone or I will rip this town apart until it rains blood.

Katherine