She's kind of right, though.
Sarah Michelle Geller is best known for her role as Buffy the Vampire Slayer. The name was pretty self-explanatory - she slayed vampires. Keep in mind, she was in high school and had little to no training or super-human powers.
So, you can slightly understand that she was a little peeved when she saw a
Wonder Woman meme doing the rounds that said, "I've never seen a woman this bad ass on screen before."
Sarah was quick to post a response on Twitter with an image of her Buffy character, with the appropriate line, "No caption necessary."

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