Around the age of five, Skagra came to the realization that God did not exist. Whereas this idea tended to cause either relief or despair in people, Skagra's reaction to this epiphany was to note that "this meant there was a situation vacant", and he spent most of his life working towards a plan hat would make him the omniscient master of the universe.
Unlike most inhabitants of Drornid, Skagra was deeply interested in his planet's history. He excavated the statue of Thorac and learned about the Time Lords, including the story of Salyavin and his ability to place his own mind in the minds of others. Skagra became obsessed with the building what he called the Universal Mind: placing his own mind into all matter in the universe. To achieve this end, he needed to release Salyavin from Shada, and to do that, he needed The Worshipful and Ancient Law of Gallifrey. Skagra drugged, kidnapped and tortured a member of the Sisterhood of Karn to force her to reveal its location: Cambridge, on Earth. As she was of no further use to him, he disposed of her by jettisoning her into space, still alive and conscious.
He also created the Ship, a sentient and top-of-the-line spaceship, partially based on stolen Gallifreyan designs. He designed its artificial personality to worship him unconditionally, having determined that this would make for the most obedient servant, though he later somewhat regretted this decision, as the Ship's constant and eager praise got on his nerves. (PROSE: Shada)
At some point, Skagra departed Dronid and set up Think Tank, a space station dedicated to the goal of creating a sphere capable of draining minds and adding the contents to its database. This was another component in his plan for the Universal Mind.
Following the creation of the Sphere, he set out to search for Shada and Salyavin. In 1979, Skagra travelled to Earth to find Salyavin. While there he obtained a copy of the mind of Professor Chronotis, in actuality Salyavin living incognito. Skagra also took the book known as The Worshipful and Ancient Law of Gallifrey, the key to Shada.
Skagra succeeded in finding Shada, but found that Salyavin had escaped long ago (and taken on a new guise as Chronotis). The Doctor and Romana II foiled Skagra's plans for the Universal Mind, and Skagra was left trapped within his rebellious ship following the Doctor's alterations to it. (WC: Shada, AUDIO: Shada, PROSE: Shada, TV: Shada) Hoping that this would eventually rid him of his character flaws, the Ship forced Skagra to watch video reports about the Doctor's life, in chronological order — a process that was sheer torture to the Doctor-hated Skagra, as soon as he began seeing the first few images of the Doctor's TARDIS in 76 Totter's Lane as a policeman walked past. (PROSE: Shada)
Skagra claimed that he was not a power hungry maniac but his actions showed that he was either lying or deluding himself, because he wanted to take over the universe — or rather, be the universe. He only allowed himself two smiles a day and usually showed very little emotion. Only the Doctor was able to cause him genuine anger and Skagra grew to hate the Time Lord immensely. He was callous, forming no sentimental attachment to his loyal ship and was happy to allow her to be blown apart once he'd found a better mode of transport. However, when Skagra was trapped inside his Ship, who wanted revenge for the way he had treated her, he begged to be freed, sobbing "Let me out! Let me out!", after realising he'd spend the rest of his life seeing and hearing stories of the Doctor. (TV: Shada)