The Lighthouse, Mercury
Ghost: I'm picking up a signal. It's faint, but it's definitely coming from the Forest. Sounds like an old Vanguard code.
Brother Vance: Perhaps you hear the final dreams of the lost.
Ghost: Uh… thanks? Very helpful. Since I can't track "dreams of the lost", how about we go find that signal?
Infinite Forest, Mercury
Ghost: The signal's getting stronger. I should be able to find the source, but there's some kind of interference.
Sagira: Signals tend to overlap, get mixed up with simulations… It can be hard to find what's real and what's not in here.
The Guardian heads towards the signal's location.
Ghost: Detecting traces of familiar Light up here. Wait… Saint-14? He's been missing for decades. Saint was one of the greatest Titans who ever lived. Hero of Six Fronts. All that power and he just… vanished. The City's still looking for him.
Simulant Present, Infinite Forest
Ghost: The signal's coming from a Vex conflux. But there's something odd. The time stream around it is unstable. I don't know anything that could do that. Get me to it. Maybe we can figure this out.
Ghost scans several confluxes.
Osiris: If Saint-14 is lost in the Infinite Forest, it's because he came here to find us.
Sagira: You can't blame yourself for every missing Guardian, Osiris.
Osiris: For him I can.
Ghost scans another conflux. An unstable conflux appears and Ghost scans it. After the scan, a force pushes the Guardian away from it.
Ghost: What was that? Light! The conflux was holding back a rift full of Light!
The Guardian defeats the Vex from the past, present, and future. Two Wayward Minds appear. The Guardian defeats the Wayward Minds.
Ghost: Vex from all times, fighting together. Like they were pulled here by the rift in the time stream – a rift Saint-14 made with his Light.
Osiris: If he still lives, then we must find him.
Ghost: Already ahead of you on that one. You start searching in here. We'll head back to the Lighthouse and see if Vance knows anything.
The Lighthouse, Mercury
Brother Vance: It's him, isn't it? The first Vanguard commander! The one who made the great Osiris leader of the Warlocks. Saint-14! He could join us here in the Lighthouse. Fight alongside you and Osiris. Turn the tide against the Vex for good. Can you imagine?! You found Osiris; you can find Saint-14. He's got to be in the Infinite Forest. With him by our side, we could succeed where Osiris failed! Well, you get the idea.