Baron Von Dool is the nickname of one or two Vanduul ace pilots. He fought battles from 2901 for different clans until 2926. His ship was spotted again in 2936, possibly flown by another Vanduul. He was recreated in the Vanduul Swarm Simulation in Arena Commander as an enemy.[1]
"If taken at face value, the Baron is one of the oldest Vanduul aces that the UEE has encountered. First logged in a battle in 2901 where it single-handedly devastated an advance team, the Baron would have been difficult to miss anyway in its customized symmetrical Scythe. A terrifying adversary with seemingly no single clan affiliation, the Baron seemed to be drawn to combat, wherever it appeared. In 2926, Naval
pilots realized that the Baron hadn't been seen in over five years. Many hoped it had died in some appropriately awful way, some lamented not being able to face it themselves, but regardless, the ace seemed to have disappeared ... for a time, at least. In 2936, the Baron's ship
reappeared, blasting through UEE security to attack settlers in Centauri system. It's unknown whether it's the same pilot, but if so, the Empire's oldest enemy found a brazen way to announce its return."
Arena Commander Manual