Paul Wesley, Nina Dobrev and Ian Somerhalder Paul Wesley, Nina Dobrev and Ian Somerhalder

Once Katherine returned to Mystic Falls in The Vampire Diaries' season finale, it didn't take her long to do some serious damage. Kissing Damon! Stabbing John!

Producers and cast say her tour of destruction has only just begun.

"I would like to see Elena take on Katherine. Elena's gone a long way," Nina Dobrev said at the show's Comic-Con panel Saturday. Despite Elena's evolution over the course of Season 1, Dobrev said it's still nice to step into Katherine's shoes. "She's badass. She gets away with a lot."

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More important than a possible battle between Elena and Katherine, however, is the conflict ahead for Damon and Stefan, as Katherine tries to pit the Salvatore brothers against each other. In exclusive footage from the new season, Katherine tells Damon that she never loved him, despite their season-finale lip-lock, and tells Stefan that she came back for him.

"This little switcheroo thing is kind of interesting. Katherine fooled Damon, but it will be really interesting to see Katherine and Stefan come face to face," creator and executive producer Kevin Williamson said, noting that the confrontation will take place in the first episode.

Katherine's return may also lead to changes in Damon and Stefan's distinct personalities. That means seeing more of "nice Damon" and the increasingly dark side of Stefan.

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"I think it's a thing that will never escape him," Williamson said. "He's going to have to come to terms with being a vampire and accepting himself for who he is. Part of accepting himself may just be drinking blood."

But no matter how dark Stefan or other characters may get this season, executive producer Julie Plec promises the change isn't necessarily permanent.

"We like to think that the darker a character goes, the closer we get to a window to the light," she said.

Things can't get much darker for Katherine, who murdered John in the final moments of the season finale. Will there be further bloodshed in Mystic Falls at her hands? Williamson would only say there would be more deaths ahead.

"It has to fit for the story," Williamson said of the upcoming fatalities. "It has to come from a place of good storytelling."

Viewers can also expect to learn more about Katherine's origins via flashbacks.

"There's another part of the story we haven't shown you," Williamson said. "It's Chapter 2, but it's also the other side. That's sort of the mystery: Where has she been? What has she been up to?"

The Vampire Diaries returns on Thursday, Sept. 9.