Katerina Petrova

Katerina Petrova, better known as Katherine Pierce, is a Petrova doppelgänger and the main antagonist of The Vampire Diaries. She is the ancestor, Döppelganger and arch-enemy of Elena Gilbert. 
She was portrayed by Nina Dobrev, who also played Elena Gilbert in the series. 
==Overview==
She is a vampire who was the lover to the Salvatore brothers, which may have caused their feud. 
==Personality==
Katherine is described as a manipulative and ruthless person. She will deceive anyone to get what she wants or for self-preservation. She is a capable manipulator and charmer, able to manipulate Arcadius and become the queen of hell. She also harbors a strong hatred for her doppelgänger Elena and has attempted to ruin her life on numerous occasions.
Despite these traits, Katherine has shown genuine affection for others, notably Stefan, and has stated numerous times that she loves him. She has also helped Damon on a few occasions, despite having told him that she didn't love him after her return. When she learned she was going to die, she fell into a deep depression and attempted to commit suicide before Stefan saved her.
==Powers and Abilities==
*Vampirism: As a vampire, Katherine possess several physical atributes and mental abilities, like the ability to compel people to do whatever she wants and turn other beings into vampires. Her physical abilities such as strength, speed, agility, durability, healing and senses all grow stronger with age and experience.
**Superhuman strength: Katherine possesses great levels of strength, allowing her to easily slaughter a normal person.
**Superhuman speed: Katherine can move at great speeds. When she runs, she appears as a blur. Her reflexes are also equally sharp.
**Superhuman durability: Katherine is highly resistant to physical damage. Normal bullets, blades weapons and even bombs cannot scratch her, but she is still susceptible to some supernatural weapons.
**Superhuman endurance: Katherine can fight her enemies for prolonged periods of time without getting tired or worn out. She also has an extremely high pain tolerance.
**Mind control: Katherine like all vampires has the ability to hypnotize humans and force them to do whatever she tells them to do.
**Immortality: Katherine is immortal and will live forever unless killed.
**Accelerated Healing: Katherine has the ability to heal herself from the wounds or diseases of others or themselves.
==Victims==
*Herself (1st time)
*Unknown man outside his quarters (in the 18th century)
*2 unnamed men (in 1864, teaching Damon Salvatore how to kill)
*Noah (Possibly/as a human)
*Caroline Forbes (as a human)
*Aimee Bradley
*Sarah (indirectly)
*Gloria
*Unnamed man outside of Pickett cemetery (feeding him to desiccated Mikael)
*Mysterious Attacker
*Massak
*Jeremy Gilbert (indirectly)
*Gregor (as a spirit)
*Mia