Zarbon
In a speculative storyline written for the made-for-television Dragon Ball Z Special 1: Bardock- The Father of Goku set before the events of the Dragonball series, Zarbon appears to have acted primarily as Frieza's advisor. It was Zarbon who is shown to have advised Frieza that it would be wise to wipe out the entire Saiyan race before they posed a threat. He is depicted as being beside Frieza as the latter killed King Vegeta and destroyed Planet Vegeta.