Let's be real, Kai's character really shook up The Vampire Diaries franchise when it comes to supernatural beings. Not only was the Gemini coven storyline incredibly fascinating and unexpected, but the fact that Kai was a siphon opened up a whole new door of possibilities for the world of magic, namely the introduction of heretics. Because Kai didn't have any magic of his own, when he turned into a vampire, he was able to defy the laws of nature and be a witch and a vampire at the same time. He was even able to heal a werewolf bite simply by siphoning the magic out of it. When Kai turned into a vampire in season six, it was truly a game changer for the entire TVD franchise.