The Vampire Diaries had many villains throughout its eight-season run. But none captured the audience's love quite like Kai Parker and Klaus Mikaelson. While Kai was a siphoning Gemini witch, Klaus was one of the original vampires. Each had their strengths and a unique personality that captivated hearts across the fanbase.

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What is it about violent psychos that fans can't help but fall in love with? Perhaps it's because everyone loves a bad boy. Whatever the case may be, these two have left their marks. Here are five reasons why Kai is the best villain and five why it's Klaus.

KAI: His Punny Twitter Account

Kai Parker in The Vampire Diaries glaring at someone off camera.

Kai's snarky sense of humor fit in so well with the likes of Damon Salvatore that it almost made the audience forget that he was a bad guy. Forever stuck in the 90s from his time in the prison world, the first thing Kai did was catch up on modern-day culture. He created a Twitter account under the name CobraKai1972.

He quickly acclimated to social media culture and drove Mystic Falls crazy with the insane live Tweeting of his violent escapades. Kai's ability to be funny while scary made him a horrific villain.

KLAUS: Family Ties

Rebekah, Klaus and Elijah standing together

Though he had many siblings, Klaus's most loyal followers were Elijah and Rebekah. They had their spats like all families, arguably more brutal, but at the end of the day, their love for one another and promise of, "Always and forever," kept them coming back to Klaus's aid.

Without their support, Klaus couldn't hold the power he did. That being said, he wasn't afraid to dagger and put his siblings in boxes to put them in their place when they began to go against him. Blood ties didn't curb his brutality.

KAI: The Sleeping Beauty Spell

Stefan holds Elena's hand in her coffin in The Vampire Diaries.

While both villains caused their fair share of deaths throughout the series that devastated the characters and the audience, Kai managed to pull off a heinous heartbreak without killing someone. In Nina Dobrev's final season, he linked Elena's life to Bonnie, leaving the main character in a magical coma that would only be broken upon Bonnie's death.

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This meant that Bonnie would never see her best friend again and that Damon was left to his own devices as he waited for Elena's return. That is truly a brilliant villain at play.

KLAUS: Klaroline Romance

Klaus and Caroline in The Vampire Diaries.

What's better than a villain that can be turned into a hero? Klaus's soft spot for Caroline gave him so many warm moments that made the audience believe he could be saved from his evil ways. It also proved that most people aren't completely heartless, not even a raging, murderous vampire-werewolf hybrid.

His ability to charm the stubborn and picky Caroline, even after what he did to Tyler and Mrs. Lockwood, showed he had a knack for making quality allies. A villain that is surrounded by powerful friends is a force.

KAI: His Dynamic With Alaric and Damon

As proven with Damon, Alaric is capable of putting the past behind him and making friends with former enemies. But when it comes to Kai, water under the bridge is not strong enough. Still, the manically gleeful siphon gets a few laughs and jabs in with his dead sister's widow in the final season when he comes back thanks to Cade's portal.

But his downfall comes in the form of two adorable little twin girls, Ric's daughter Lizzie and Josie. He can't win them all.

KLAUS: The Original Hybrid

Klaus Mikaelson became the first of his kind when Esther created the vampire spell that turned him and his siblings immortal. But the secret of his true werewolf lineage came to light when Klaus undid the binding of those powers and combined his two supernatural sides.

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Claiming centuries of power from being an original vampire and the capabilities of his father's werewolf heritage made him an indomitable foe. It also gave him the power to cure his enemies of werewolf bites if he was feeling gracious.

KAI: He's a Sociopath

Kai did not care about or love anyone or anything. This made him a dangerous villain, as the only thing he had to lose was his life. But having survived the prison world his family sent him to in the 90s gave him a cruel edge that turned him fearless.

Without that ability to love or care about others, Kai was a villain in the truest sense of the word. Without anything to lose, Kai didn't need to exercise caution in his mad attempts to kill everything in sight.

KLAUS: Sympathetic Backstory

Klaus and Rebekah in the Middle Ages in The Vampire Diaries

Knowing how Mikael treated him all his life, it was easy for Klaus to play the terrible dad card to garner sympathy. That ability to make his enemies feel even a hint of pity for him gave him the leverage he needed to break down their defenses.

His humanity made him weak in Mikael's eyes, but it afforded him the strength he needed to fight and win. Without a sympathetic backstory, Klaus wouldn't have made such a dynamic villain. That's what made the fans love him and led to The Originals.

KAI: Siphon Powers

With the ability to siphon all magic, Kai is arguably the more powerful villain. He may not have had magic or powers of his own, but if he gets his hands on magic, then it gives him a leg up he needs to win a fight.

In a fight against Klaus, all Kai would need to do is get a hold of the immortal to siphon his original vampire magic and render the Mikaelson useless. Being a siphoner is what made him so hard to kill for so long.

KLAUS: Ripper Maker

Klaus and Stefan in a bar in the 1920s

Klaus prides himself on being a vicious monster that can rip out hearts and throats without remorse. But his ability to turn those around him into the same kind of monster makes him particularly scary. When he comes to Mystic Falls and steals Stefan away from his friends and family, he forces the good Salvatore into his old Ripper ways.

Worse, he does it simply to toy with Elena and Damon because he can. A monster that makes more monsters is a dangerous enemy.

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