A Pothradian scientist, Pothradians being a race that lives together with nature. He looks young on the surface, but he's eighty-two years old. Normally, Pothradians seldom appear before human beings, but Pernagi didn't follow suit. He was found by Seldous' party at the ruins of an ancient weapon. He offered to repair it, and it became the Admonisher, a devastating weapon that could float in the sky.
Pothradians can see the Ley Line and wavelengths in everything -- people, plants, objects. Because they are trained to see things that are not visible, they can see the wavelengths of the Ley Line. They migrate every few years to live with the Ley Line where it is strong.
Pernagi said that the Admonisher needed to be taken down because the Dragon Orb which powers it was consuming the life of the planet and causing it to become barren. Pernagi was ordered by Isaac to research another energy source for the Admonisher, and Pernagi quit it in the middle of it because it costed humans lives. Isaac had pursuers go after Pernagi to take that research information. If they received that research, they then had to kill Pernagi to keep things quiet. He couldn't return to the Pothradians because he was exiled from them. Randall saved him from pursuers and he ran to Jaergen and was sheltered there. Fanille met him when she was a child; he showed her Pothradian books and she read them. Although she didn't understand them, she remembered them.
In the Peace Maintenance Brigade, eventually Fanille researched the same thing that Pernagi did, vital energy, and it became unecessary to pursue Pernagi.
He was recruited by Zeonsilt's group and worked in Fanille's lab at the PMB, and he helped them with magic and science projects. He performed the magic which froze Zeonsilt's body in time so that he wouldn't be in danger of dying until Fanille could find a cure.