The Grand Serpent

His Supremacy, the Grand Serpent was a political figure on Inston-Vee Vinder's home planet.

The Grand Serpent met the Alforia to discuss terms. Once the official meeting was concluded, he ordered Vinder to cease recording and then demanded the Alforia handover five dissidents being sheltered in their territory to face trial, and for another four, all relatives of his critic Frey Sampor, to suffer a fatal accident. Inston-Vee Vinder reported the incident, resulting in him being reassigned to Observation Outpost Rose. (TV: Once, Upon Time)

He positioned himself on Earth in 1958 in order to assist the founding of a new organization known as UNIT. In 1967, after being identified as an alien, he began a streak of assassinating those who stood in his way. In 2017 he encountered Kate Stewart, informing her that UNIT funding was being cut. When she retaliated by threatening to expose his history with the organization, he attempted to kill her by leaving a bomb in her house. (TV: Survivors of the Flux)

Trivia

 * While accusing him of messing with UNIT, Kate Stewart refers to "tampered archives", "deleted incidents", and "changes to reports from the last 5 decades", despite 1958-2017 being 59 years. This is possibly intended as an explanation to the UNIT dating controversy. (TV: Survivors of the Flux)