Xyla Mason makes her first appearance in chapter 1, "3007." She is the daughter and sister of the Mason family.
Xyla was originally born and raised at the International Space Station. When living conditions began to deteriorate there, Xyla and her family ventured to Planet X — Planet Nibiru — as a potential new home.
After the humans lost their war with the Nibirian people and faced enslavement, the Mason family managed to escape and settle on Earth. Xyla's story is part of the larger Mason family narrative of survival, displacement, and resilience across worlds.