Vibax was a Time Lord scientist sponsored by the Celestial Intervention Agency.
He was tasked with creating weapons for the Last Great Time War and created the Orrovix. He complained at the lack of funding to upgrade his equipment. (AUDIO: Assets of War) Vibax eventually regenerated, with Veklin later complaining they got worse with every regeneration.
Rassilon threatened Leela that unless she cooperated with his War Room, he'd hand her over to Vibax to experiment on her however she saw fit. Vibax supplied a planet killer device for the Eleventh General, Veklin and Leela to use to destroy Freme. (AUDIO: The Last Days of Freme)
Vibax was eventually killed in an explosion engineered by Cato Kelgoth as part of his revenge against the Eleventh General and Cardinal Ollistra. (AUDIO: The Passenger)