چاللیا بیولل

Bull's sole appearance was in episode 39 of Mobile Suit Gundam. He is first shown meeting Admiral Gihren Zabi after he returned from Jupiter. Gihren believes Challia to be a newtype and believes he has strong abilities that can benefit Zeon. Bull was assigned to work under Kycilia Zabi and headed to Granada where he was assigned to operate the Braw Bro. Kycilia speculated that based on his abilities, Challia may have replaced Lalah Sune as pilot of the Elmeth mobile armor. The Braw Bro then headed out and was stationed on Char's Zanzibar where Challia met Char and Lalah. Bull would later pilot the Braw Bro in battle against the Earth Federation's RX-78-2 Gundam and fellow Newtype pilot Amuro Ray. The battle would last a little under 10 minutes before the Braw Bro was destroyed and Bull was killed.

In Kidou Senshi Gundam: GQuuuuuuX8, Challia Bull forms a two-man Mav team with Char Aznable, and pioneers this style of mobile suit combat. Several years after the Zeknova incident where Char disappeared, he continues to serve in the Zeon military all while searching for the Mav he lost.