When Jayna was young, her father trained her and her brother in combat. One day, he sent Jayna and her brother in the outlands to fulfill a task. They only had one oxygen supplier, so Jayna had to fight her brother for it. Jayna completed the task but her brother did not survive. She wanted to go back and find him but her father did not allow her and gave Jayna the necklace of House of Zod.Patel, Lina (writer), Ramsay, Julius (director) (April 18, 2018). "House of Zod". Krypton. Episode 5. Syfy.
As Primus, Jayna-Zod commanded the Sagitari of Kandor City. Her daughter, Lyta-Zod, followed her into the Military Guild. Despite Lyta being intended to bind with Dev-Em, Jayna was aware of her daughter's secret relationship with Seg-El.
During a Sagitari training session, Jayna chose Lyta to spar with her, giving the choice of weapons or hand-to-hand combat to Dev-Em. During the fight, Jayna made Lyta cry for mercy then admonished her for the act since mercy was a weakness. She drove a blade through her daughter's hand. Jayna was later present at the trial of Charys-El. When Ter-El grabbed a weapon, Jayna killed him, then killed Charys when she tried the same, actions for which she scolded by Daron-Vex.
After Lyta questioned the Sagitari's future rankless initiative, Jayna shot her down, claiming she had neither the rank nor right to question her. Later, Lyta challenged Quex-Ul to a duel to the death, causing Jayna to question her daughter's actions, visibly shaken and afraid by her choice. She oversaw the fight, surprised when Lyta ultimately won. Despite her qualms, she presented Lyta with honorary badges, granting her the rank of commander.
- "House of El"
- "The Rankless Initiative"
- "The Word of Rao"
- "House of Zod"
- "Civil Wars"