1. she change both salvatores and we got to see them.
2. brought damon the cure for the werewolf bite.
3. is just amazing with her looks
4. has a unique style and personality
5. Has great taste in boys. (stefan,damon and maison)
6. SHES A Petrova DOPPELGANGER.
7. WE ALL प्यार HER.
8. turned caroline :)
9. might win stefn over so delena could finally happen ♥
10. makesthe दिखाना just awesome because her and elena look alike along with tatia.
Then theres the flash backsand the past with klaus. withput that past and her hanging herself no originals would be on the show. if katherine had died back then the दिखाना would just be about the प्यार त्रिकोण, त्रिभुज which is awesome but katherine just makes the show!~imagine no originals या doppelgangers and rose? that would not be TVD!!!!!!