In Season 6, we see how Callum and Rayla get their hands on three Quasar diamonds, but one of them is fake. Rayla is only able to save her adopted father, Runaan, and her actual parents sacrifice ...

Celestial Elves prophecized and envisioned that Callum's soul is in danger because of his use of black magic, and he can fall prey to darkness in the future, with Rayla as his only guiding light.