Vulpina was empress of Amtor.
While Empress, Vulpina found the caves containing the preserved Thraskins and met Vepaja. Though she agreed to help him, Vulpina instead released the animals and used the Thraskin as slaves. She made the caves forbidden to protect her secret deal.
This continued for 6 years until her scientist Corvina started to figure out what had happened. She secretly killed Corvina while she was collecting samples and blamed a Shanghorn attack. After the Sixth Doctor, Jago and Litefoot happened to come to Venus at the same time, Vulpina had them captured and brought to Amtor. After seeing Jago trying to entertain some captured Thraskin, she had him brought to her throne room for her own entertainment. Her new scientist, Ursina, studied the Doctor and Litefoot at the same time. The Doctor and Litefoot were able to prove that Corvina had been murdered; Vulpina decided they had to be silenced and sent Felina to kill them. Jago was able to warn them and Ursina, the Doctor and Litefoot escaped Amtor for the caves. Vulpina took Jago and her royal guard to follow them.
When they got to the caves, Vulpina planned to kill them all until Vepaja set up a force field to protect the Doctor and Ursina. Instead, Vulpina withdrew and set up a series of explosive to trap the Doctor and Ursina inside the cage. Jago tried to threaten her with a palmed explosive, but Jago relented when Vulpina threatened to kill Litefoot. The explosive were set off, but Vepaja protected the Doctor and Ursina and considered it an act of war. While Vulpina was leaving, Vepaja attacked Amtor with a storm, causing it to crash, and then sent a herd of Shanghorn to kill the survivors. When Vulpina demanded the guards protect her instead of the city, they revolted and locked her in Amtor's zoo. (AUDIO: Voyage to Venus)