Tesla is a male Invid scientist that served within the forces of the Regent. He became an unlikely ally to the cause of the Sentinels after being held captive by them, and was even able to evolve past the point of the Regent.
According to one source, Tesla was put in charge of Tirol by the Regent, and was told that failure in his mission would mean death. (Robotech II: The Sentinels) Other sources suggest that this task was actually given to Obsim, and that Tesla was doing other activities at the time. (Robotech II: The Sentinels)
According to these sources, the Regent decided to appease his wife the Regess by sending Tesla to gather sentient specimens from his new empire, and chose Tesla to pilot a makeshift starship to each of the planets captured by the Invid's conquests in the Local Group. The vessel was a mix of machines from these worlds, and was piloted by Karbarrans. The Regess, surprisingly, took an interest in the zoo being constructed, particularly during their mission to take hostages from Praxis. She considered the species to be a proud warrior race, and took some with her to conduct "experiments" on.
Soon, however, the ship was attacked and over-taken by a resistance force known as The Sentinels. Tesla was held captive, kept in a cage at all times. Neither The Regent or the Regess realized that Tesla had been captured or that he was missing -- each angrily presuming that he had joined the other. The Sentinels soon heard of the Liberation of Tirol from the Invid by the Robotech Expeditionary Force, and would seek them as an aide in their plans to liberate their own worlds from the threat. After allying with them, they showed Rick Hunter and Lisa Hunter the captured Tesla, who remained their prisoner.
Later on, the Sentinels and their Human allies launched their first mission in freeing the industrial world of Karbarra. During this time, Admiral Lisa Hunter decided to entice the aid of Tesla by threatening to kill him with an explosive collar. Their ruse involved Tesla pretending that he had captured the Sentinels and thus lulling the Invid Brain in charge of the garrison to lower its guards. This allowed the Sentinels to stage a surprise assault and conquer the planet with Tesla worrying about his standing with the Regent as a result of the incident.
At this time, the Perytonian Burak attempted to learn whatever knowledge Tesla had in freeing his homeworld of Peryton from its curse. Tesla agreed to help him in exchange for his assistance. Burak brought with him fruits of the Flower of Life, which Tesla began to consume despite it being forbidden by his race. (Robotech II: The Sentinels: Traitors in the Midst)
By eating the Flowers, his body began to go through a forced evolution - he first grew another finger, (Robotech II: The Sentinels: The Dance of Death) then evolving into a more superior as well as larger form where he planned his escape. After being trapped on Praxis, Tesla and Burak volunteered to help save the Sentinels by boarding the Beta Fighter in order to reach the destroyed Farrago's drive unit to get help.
However, Tesla and Burak betrayed the Sentinels where they turned against Janice Em as well as Jonathan Wolfe. Despite their initial success, Janice had reprogrammed the drive to take them to the REF where they arrived at a point where the Expeditionary Force was meeting with the Regent in planned diplomatic encounter. Whilst held in captivity, Tesla managed to escape the guards and intended to meet with the Regent in order to enlist his masters aid. However, Tesla became enraged as being imprisoned for so long by the Sentinels and killed his master - unaware that he was in fact a clone. The shocked Tesla believed that the fruits of the Flower of Life had warped his mind and he quickly departed before anyone witnessed the act. He was not aware though that the true Regent had witnessed his servants betrayal. Tesla remained in the company of the Sentinels as their unwilling prisoner but began to plot to take over the Invid race and became an equal to the Regess herself. He intended to accomplish this by consuming more fruits of the Flower of Life which were increasing his size and powers.
With Garuda liberated, two Invid scientists were imprisoned alongside Tesla who killed them with his greater strength when they tried to eat the fruits of the Flower of Life given to him by Burak. During the mission to Haydon IV, Admiral Hunter intended to exchange Tesla for the captured Rem. When learning of this, Tesla journeyed with a bodyguard detail where he mentally manipulated the pilots in order to reach the Invid Hive to pillage it of its stores of the Flower of Life. His shuttle was later shot down during the battle between the Regent's forces and Sentinels.
He was returned into the custody of the Sentinels where he now sported an even larger, more evolved and humanoid based form with greater abilities. The Sentinels at this point pushed to free Spheris where Tesla volunteered to help by taking control of the garrison on the planet as his powers were great enough to dominate other Invid. Though he claimed that he wanted to help, secretly he intended to use the mind controlled Invid as part of his push to lay claim to the throne of the Regent. However, his powers were not as strong and he only managed to take control of only half the garrison, which forced the Sentinels to battle the other half in order to free the Spherisians.
Behind the Scenes
The video material and background notes in Robotech Art 3 for Robotech II: The Sentinels states that Tesla would originally have been stationed on the conquered world of Tirol to find the Protoculture Matrix. In this setting, he would have been captured by the REF and been a prisoner where he would have plotted the downfall of the Regent whilst making plans to become the new ruler of the Invid. Notes in the book state that Tesla is quite young by Invid standards and is 117 years old. Its highlighted that Tesla is an evil personality like the Regent but for different reasons. The section states the Regent is an evil dictator caused by the system similar to Perone and Marcos whilst Tesla is a malevolent entity more like Rasputin and Cagliostro. This story is seemingly set-up in the opening episodes, as Tesla is put in charge of Tirol.
Elements of the story were seemingly incorporated into Waltrip's Sentinels comics but substituted Tesla for Obsim, with Tesla himself being captured on the Farrago. According to the comic and novel timeline, Tesla would have died freeing Burak's homeworld from its curse. The canonicity of this version of Tesla in the current continuity is unknown, as the sequel series Prelude to the Shadow Chronicles makes no mention of him. This also leaves his fate open, as Sentinels had ended with a cliffhanger with the character.