===Time with The Five===
Tesla was a famous scientist, though Druitt suggests he leeched off Edison and cheated Marconi (which is a lie). Nikola, nevertheless, enjoyed working together with the group at Oxford, but felt they all changed when they got their powers, whereas he felt he had found out who he really was. Nikola also became a great friend and admirer to Magnus during her studies of Abnormals; to the point he loved her "more than that lunatic Druitt ever did". While the rest of the five gained their own unique abilities that either reflected on their personality or improved them, Tesla's reaction to the source blood was the most bizarre. Unknown to the Five, or even to himself, one of Nikola's ancestors had been a Vampire, and the dormant genes had been passed down to Tesla. These genes were awoken by being exposed to the Source Blood. As well has gaining the ability to cast streams of electricity at will, he also developed vampiric characteristics including enhanced speed, strength and agility, immortality, regenerative (healing)powers and a supposed blood-lust. Helen was able to help him overcome and control the thirst for blood by developing a special medication for him to take daily.

Tesla is able to change from human form in to his vampric side at will, and can even stop the change at certain stages. When he fights Ashley at the start of season 2 instead of becoming a full vamp (as seen in the first season when he is up against the soldier and his eyes simply go black) he just grows claws to fight Ashley. He also mentioned to Helen, when they meet up again after 60 years apart,as he defended her from one of the vampire-soldiers he created by letting his own vampiric side out that he simply "became a little too excited" by the blood and promised her he was still on the medication she developed for him.