Part 01: I Would Have Been Your Daddy...

GRUNT ACR1:

Gyiay! Ahhhhh! Uh-ooh-uh-ooh-uh-ooh!

FOE HAMMER:

This is as far as I can go.

CORTANA:

Roger that. We'll be able to find our way to the control center from here.

FOE HAMMER:

Good luck. Foe Hammer out.

(Once you clear the first of the circular rooms)

CORTANA:

The Covenant presence here is stronger than I anticipated. They seem to have the entire region secured.

(Once you reach the first bridge)

CORTANA:

Interesting... the weather patterns here seem natural, not artificial. I wonder if the ring's environment systems are malfunctioning... or if the designers wanted the installation to have inclement weather.

SERGEANT ACR1:

This is Fire Team Zulu requesting immediate assistance from any UNSC forces. Does anyone copy?

CORTANA:

I didn't think there were any human forces left on this part of the ring.... (Radio) Cortana to Fire Team Zulu, I read you. Fire Team Zulu, this is Cortana. Hold position. We're on our way.

SERGEANT ACR1:

Roger that. Make it quick.

(When you reach the bottom of the chasm and meet up with Fire Team Zulu)

MARINE ACR1:

Glad you could join the party, Sir!

(When you reach the second group of Marines fighting near the Scorpion and clear the area)

MARINE ACR2:

Enemy forces eliminated. The area's secure.

MARINE ACR3:

Aw, crap. Let's get the hell outta here, man! Somebody call the dropship!

Sergeant Johnson:

You stow that garbage right NOW, mister. You're a Marine, so act like it, dammit. We've got a job to do.

CORTANA:

Negative, team. No evac available at this time. But the Chief and I could use some assistance.

SERGEANT ACR1:

(Random Dialogue)

-Okay, Marines. Time to pay back the Chief for pulling your sorry tails out of the fire. -etc.

(As you reach the second large open area, where one Wraith hovers on the ice and another lurks on top of the cliff at the far end of the canyon)

(There are at least three choices here-how the game chooses which one to play is unknown. It seems to be random, as a checkpoint right before this area will result in different dialogues after restarting. It is unknown how many there are total; the Halo Story Page has recorded thre of them (thanks to funkmon for the third).)

(Type 1)

MARINE ACR4:

Bloody hell! Enemy forces have armor support... it's time to earn our pay.

CORTANA:

The Covenant placed their tanks to defend the entrance to the tunnel.

(Type 2)

MARINE ACR5:

Enemy mortar tanks sighted at my position... it's gonna be a busy day.

CORTANA:

The Covenant placed their tanks to defend the entrance to the tunnel.

(Type 3)

MARINE ACR5:

Dang, they got armor support! Watch out for those tanks!

CORTANA:

The Covenant placed their tanks to defend the entrance to the tunnel.

(When you've toasted the first Covenant Wraith.)

MARINE ACR6:

Looks like that armor wasn't so tough after all! Let's mop up the rest of 'em!

(When you reach the large interior cavern and engage the Covenant inside)

MARINE ACR7:

More Covenant sighted!

MARINE ACR8:

Man, these guys are like cockroaches!

(As you reach the long rock tunnel leading up from the cave system back to the surface)

Part 02: Rolling Thunder

(As you clear the area containing the fourth Wraith of the level)

SERGEANT ACR1:

You monkeys almost look like golden boys!

MARINE ACR9:

Damn straight!

(As you come across two Hunters playing hell with a squad of Marines, where the path switches back and goes down to a frozen river leading to the cave to the last area of the second chasm)

CORTANA:

I thought the Covenant had eliminated all the Marine forces in this area.

(As a Covenant dropship appears from behind the cliffs and drops in on the ridge you just descended from)

MARINE ACR10:

Anybody else hear that? Aw, man... Covenant dropship inbound, take cover!

MARINE ACR11:

The Covenant are dropping in behind us! We're trapped!

(As you near the switchbacks leading up to final area of the second chasm)

MARINE ACR12:

Whoa, Sir! The Covenant are dug in up in those rocks! They've got us pinned down here!

CORTANA:

We need to get up this ridge. (Radio) Marines, hold your positions. We'll handle those guns. (Off radio) Master Chief, we should scale the ridge and get below those stationary guns.

MARINE ACR12:

I'm in no hurry for a heroic charge on those guns, Cortana. Holding position.

(As you reach the door leading into the cliff face)

CORTANA:

Fire Team Zulu. I've sent a distress signal tagged with your current position. Hold her and await evac. The Master Chief and I are going to continue on inside.

SERGEANT ACR2:

That's affirmative! Fire Team Zulu out!

(As you clear the final area before the third chasm)

CORTANA:

Resistance appears to be increasing. We must be close to the control center.

Part 03: If I Had A Super Weapon...

CORTANA:

Analyzing. This must be the control room. Subtle. The entrance to the control room is at the top of that pyramid structure. Bring me up there and I should be able to get us inside.

(As you open the door to the last leg of the hallway leading to the control center)

CORTANA:

Scanning. Covenant forces in the vicinity have been eliminated. Let's move on to Halo's control room.

(As you open the final door-cinematic)

CORTANA:

This is it. Halo's control center.

(The Master Chief walks through the door and to a control panel at the center of a circular glass walkway projecting into the middle of a massive open chamber. A holographic map of Halo surrounds a smaller holographic map of the system, which shows Basis and Threshold, and Halo itself between them)

CORTANA:

That terminal, try there.

(The Master Chief unplugs Cortana's chip from his helmet and places Cortana's chip in it. A moment later she above the display, data streaming out from her in all directions. Her eyes are now red.)

MASTER CHIEF:

You all right?

CORTANA:

Never been better... you can't imagine the wealth of information. Knowledge... so much... so fast. It's glorious!

MASTER CHIEF:

So... what sort of weapon is it?

CORTANA:

What are you talking about?

MASTER CHIEF:

Let's stay focused. Halo... how do we use it against the Covenant?

CORTANA:

This ring isn't a cudgel, you barbarian, it's something else... something much more important. The Covenant were right... this ring... it's Forerunner. Give me a second to access... yes, the Forerunner built this place, what they called a, "fortress world," in order to... no, that can't be. Oh, those Covenant fools...they must've known, there must have been signs!

MASTER CHIEF:

Slow down. You're losin' me.

CORTANA:

The Covenant found something, buried in this ring, something horrible, and now...they're afraid.

MASTER CHIEF:

Something buried? Where?

CORTANA:

The Captain, we've got to stop the Captain!

MASTER CHIEF:

Keyes? What do we-

CORTANA:

The weapons cache he's looking for, it's not really-we can't let him get inside!

MASTER CHIEF:

I don't understan-

CORTANA:

There's no time! Get out of here, find Keyes, stop him! Before it's too late!

(The Master Chief turns and runs from the control room)