14. Katerina Petrova/Katherine Pierce, as seen on The Vampire Diaries, portrayed by Nina Dobrev
Katherine Pierce gives me so many feelings, I'm not sure how coherent this is going to be. Consider this your warning.
Despite her status as villain, I consider Katherine to be one of the most tragic characters on this show. At sixteen, she gets pregnant out of wedlock and, in one fell swoop, not only has her daughter taken away from her but it is cast out of her family. While we don't know how she ended up in England, her attempt at finding something stable, something like love, leads her to Klaus, who wants to sacrifice her. I feel like it's important to recognize that Katherine is barely eighteen when she runs from Klaus and tricks Rose into giving her blood so she can turn herself by committing suicide.
A lot is written about Katherine's selfishness and Machiavellian tactics, but I don't view Katherine as particularly evil. Katherine knew she was going to die; it was only a matter of letting Klaus control when that was or controlling it herself. For the majority of her life, Katherine had no power and was at the whims of whoever did have it: her father, Klaus, even Elijah. Katherine became a vampire and spent 500 years outsmarting a vampire who is considered to be the "smartest" (for whatever reason) and did so to her advantage.
I think Mystic Falls 1864 is the first cracks in Katherine's veneer. After running for centuries, Katherine meets two brothers who are desperately in love with her, and, as we know from 1492, Katherine once absolutely believed in love. I think Damon and Stefan represented all that was simultaneously taken from her and that she deprived herself of, and, while she's certainly jerked them around since then, it's not out of character for Katherine, for whom survival is paramount.
Katherine claims to hate Elena, but her behaviors say otherwise. In some ways, I think Katherine is jealous and even woried about Elena; Katherine knows what it is like to be Elena, to be persecuted for blood you can't control, and Katherine's entanglements with Elena and the Salvatores show she's not quite as closed off as she once was. If anything, her insistance at the end of 3x09 for Stefan to get mad, to get revenge, shows how much she is invested in, Stefan's survival.
But what makes Katherine truly amazing is she spent 500 years on the run, and no one has ever truly kept her down. She might end up in the tomb temporarily or end up in Klaus's clutches, but Katherine always survives, always escapes, always lives to fight another day and continue to show everyone else just how much Petrova fire she has.
An that's pretty kick-ass.