The Vanguard had decided to give a Dark Guardian a chance in redeeming themself. You had pleaded the Vanguard for forgiveness for turning towards the Darkness rather than the Light. Commander Zavala was hesitant, almost declining you. Though eventually he gave in, seeing this as an opportunity in learning a bit more about the Darkness and of course, getting a friend back.

No one knew if you were playing some sort of trick or if you were actually serious about turning back to the Light. It was a risk... and risks were the thing Cayde-6 liked taking. Cayde offered to be a mentor to you. It didn't matter what class you were, Cayde wanted to mentor you; thinking it would be fun to have a Dark Guardian as an ally.

"So... would ya mind if I called ya, Rookie? Wait... no.. you technically aren't a Rookie since you used to be a Guardian that followed the Light... but now you follow the Darkness... and now you want to follow the Light again...." He muttered under his breath.

"Damn, pick a side, would ya?" He said.