GHOST: I've been combing the Cryptarch's records for anything on the Temple of Crota. Listen:
MASTER RAHOOL: Long ago, the Moon fell to Crota. He wielded a sword so dark it drained whatever Light it touched. Now, Crota sleeps, but the Sword does not. The Warlocks believe the Sword is in a chamber guarded by the Swarm Princes. If you face them and steal the sword, we can see that it is never wielded again.
Archer's Line, Ocean of Storms, Earth's Moon
GHOST: The only way to destroy the sword is to kill its makers, the Swarm Princes. One of them is said to guard a ritual site near the Hellmouth. We'll challenge him first.
The Ritual Site
GHOST: This is where we'll find him. I hope you're ready.
The Guardian kills Banuk, Ur Prince.
GHOST: One down. I'll lead us to the others.
GHOST: Not to unsettle you, but I'm tracking the Sword by the Light of the Guardians it's killed. It's further below.
GHOST: The Sword is close. I can feel its power.
The Guardian finds the Sword of Crota.
GHOST: Clear them out!
GHOST: Grab the Sword. That should lure them out.
The Guardian grabs the Sword.
GHOST: Careful. Its power is... dark.
GHOST: Lots of movement, all around us! The Princes are coming for the Sword.
The Guardian kills Garok, Xol Prince, Dakoor, Yul Prince, and Merok, Eir Prince.
GHOST: The Sword is gone. They say that was one of the most powerful weapons the Hive ever wielded against us. The Cryptarchs won't believe this.