Ezekiel-254 was promoted to Lieutenant in the UNSC Navy by 2559, and was the second in command of all Spartans. He personally oversaw Katana team's mission to Zeta-9 to investigate an old emergency signal. It is known that he was one of the Spartans assigned to assist the Sangheili during the Rift Crisis, in which hundreds of Sangheili newborns were kidnapped. He is one of the few humans to have ever set foot on Sanghelios.