Blair Waldorf may rule the Upper East Side, but best not take a certain newcomer lightly.

According to Entertainment Weekly, the Katie Cassidy-Leighton Meester death match is so on this season, as Stephanie Savage reveals that Cassidy’s character will be a vixen who tangles with several characters, including the show’s reigning Queen B.

“When we had the idea for the role we knew there was going to be a really short list of actresses who could actually stand up to Blake [Lively] and Leighton on the screen,” says the show's executive producer. “Katie Cassidy felt like a great choice.”

We couldn't agree more, and can't wait to see what they come with for her.

Steve Marsi is the Managing Editor of TV Fanatic. Follow him on Google+ or email him here.