Halo Alpha
Halo Alpha

Re-activate the weapon at the heart of Halo... and learn the truth.

Two Betrayals is the eighth campaign level of Halo: Combat Evolved. It is set in the same location as Assault on the Control Room, but this time John-117 travels in the opposite direction. The objective is to destroy three Phase Pulse Generators while fighting three other factions of enemies striving towards everyone else's destruction.


The Master Chief, after teleporting back to the Control Room, proceeds to activate Installation 04. However, Cortana, who after spending twelve hours in the control room has discovered Halo’s true purpose, stops him just in time. After stealing the Activation Index, she tells the Chief that Halo will wipe out all life in the galaxy, and turns the Chief against the Monitor. Spark sends Sentinels to take the Spartan's head, and the AI inside his helmet. After destroying the Sentinels in the Control Room, Cortana tells the Chief to destroy three Phase Pulse Generators to buy some time, in case the Monitor and his Sentinels find a way to activate Halo's firing systems without the index. While Cortana tries to locate the Pillar of Autumn's crash site, the Master Chief must hijack a Covenant Banshee and set out to destroy the generators. After destroying the third pulse generator, Cortana teleports the Master Chief to a Covenant cruiser: the Truth and Reconciliation. There the level Keyes begins.


Two Betrayals[]

{Original Cutscene} {Anniversary Cutscene}

Long shot of the Control Room. Master Chief and 343 Guilty Spark teleport in, obviously in the middle of a conversation, explaining something about the Flood.

  • 343 Guilty Spark: "...which means that any organism of sufficient mass and cognitive capability is a potential vector."

Master Chief pauses as though sensing something is not quite right.

  • 343 Guilty Spark: "Is something wrong?"
  • 343 Guilty Spark: "Splendid. Shall we?"

Master Chief and 343 Guilty Spark move up to the main control panel.

  • 343 Guilty Spark: (random humming) "Unfortunately, my usefulness to this particular endeavor has come to an end. Protocol does not allow units with my classification to... perform a task as important as the reunification of the Index with the Core. That final step is reserved for you, Reclaimer."

Master Chief takes the Index, and puts it into a slot on the console. Lights and holograms appear, but then fade.

  • 343 Guilty Spark: "Odd. That wasn't supposed to happen."
    Two betrayals

    Master Chief activating the array with 343 Guilty Spark

Cortana suddenly appears over the console.

There is a flash of light, and 343 Guilty Spark is thrown back, and down to the ground.

  • Master Chief: "Cortana!"
  • Cortana: "I've spent the last 12 hours cooped up in here, watching you toady about, helping that thing get set to slit our throats!"
  • Master Chief: "Hold on now, he's a friend."
  • Cortana: (Mockingly) "Oh! I didn't realize. He's your pal, is he? Your chum? (angrily) Do you have any idea what that bastard almost made you do?!"
  • Master Chief: (Patiently) "Yes... activate Halo's defenses, and destroy the Flood, which is why we brought the Index to the Control Center."
  • Cortana: "You mean this?"

Index hologram appears in Cortana's hand.

  • 343 Guilty Spark: "A construct?! In the Core?! That is absolutely unacceptable!"
  • Cortana: "Sod off!"
  • 343 Guilty Spark: "What impertinence! I shall purge you at once!"
  • Cortana: (smiles nastily) "You sure that's a good idea?"

Cortana's avatar absorbs the Index.

  • 343 Guilty Spark: (outraged) "How... how... how dare you! I'll--"
  • Cortana: "Do what? I have the Index! You can just float and sputter!"
  • Master Chief: "Enough! (The Chief brings both hands up in the middle of them as if to stop a fight, then turns back to face Cortana.) The Flood is spreading. If we activate Halo's defenses, we can wipe them out."
  • Cortana: "You have no idea how this ring works, do you? Why the Forerunners built it? Halo doesn't kill Flood, it kills their food. Humans, Covenant, whatever. We're all equally edible. The only way to stop the Flood is to starve them to death. And that's exactly what Halo is designed to do: Wipe the galaxy clean of all sentient life. You don't believe me? Ask him!" (Points at Spark.)

Master Chief hesitates, and then turns to 343 Guilty Spark.

  • Master Chief: "Is it true?"
  • 343 Guilty Spark: (pauses) "More or less. Technically, this installation's pulse has a maximum effective radius of twenty-five thousand light years. But, once the others follow suit, this galaxy will be quite devoid of life, or at least any life with sufficient biomass to sustain the Flood." (Pause) "But you already knew that... I mean, how couldn't you?"
  • Cortana: "Left out that little detail, did he?"
  • 343 Guilty Spark: "We have followed outbreak containment procedure to the letter. You were with me each step of the way, as we managed this crisis."
  • Cortana: (alarmed) "Chief, I'm picking up movement!"
  • 343 Guilty Spark: "Why would you hesitate to do what you have already done?"
  • Cortana: (urgently) "We need to go, right now."

Four Sentinels float up behind 343 Guilty Spark, their beams aimed menacingly on the Chief.

  • 343 Guilty Spark: "Last time, you asked me, if it were my choice, would I do it? Having had considerable time to ponder your query, my answer has not changed."

Master Chief looks around at the Sentinels, and backs towards the panel. He takes Cortana's disk out of the console, and inserts it into his helmet.

  • 343 Guilty Spark: "There is no choice. We must activate the ring."
  • Cortana: (urgently whispers in Master Chief's head) "Get - us - out - of - here!"
  • 343 Guilty Spark: "If you are unwilling to help, I will simply find another. Still, I must have the Index. Give your construct to me, or I will be forced to take her from you."
  • Master Chief: "That's not going to happen."
    Two betrayals 2

    The Master Chief aiming his Assault Rifle at the Monitor

  • 343 Guilty Spark: "So be it." (to the Sentinels) "Save his head. Dispose of the rest."

343 Guilty Spark teleports away, and his Sentinels attack


  • Cortana: "Look out!"

After the Sentinels are destroyed:

The Gun Pointed at the Head of the Universe[]

  • Cortana: "We can't let the Monitor activate Halo. We have to stop him - we have to destroy Halo. According to my analysis of the available data, I believe the best course of action is somewhat... risky. An explosion of sufficient size will help destabilize the ring, and will cut through a number of primary systems. We need to trigger a detonation on a large scale, however. A star ship's fusion reactors going critical would do the job. I'm going to search what's left of the Covenant battlenet, and see if I can locate the Pillar of Autumn's crash site. If the ship's fusion reactors are still relatively intact, we can use them to destroy Halo."

Once outside, into the canyon

  • Cortana: "I haven't located the crash site yet but we need to buy some time, in case the Monitor or his Sentinels find a way to activate Halo's final weapon, without the Index. The machinery in these canyons are Halo's primary firing mechanisms. They consist of three phase pulse generators that amplify Halo's signal, and allow it to fire deep into space. The power levels are enormous. I can't even begin to calculate the pulse's range. So, if we damage or destroy these generators, the Monitor will need to repair them before Halo can be used. That should buy us some time. I'm marking the location of the nearest pulse generator with a nav point. We need to move in and neutralize the device."

Once down to ground level:

  • Cortana: "Wait. We should commandeer one of those Banshees; we'll need it to reach the pulse generator in time."

Once in the Banshee:

  • Cortana: "Good, let's get moving. The nav point marks our target."

Once you reach the room the generator is in:

  • Cortana: "That's the pulse generator. The center core is the signal amplifier. That's what we need to shut down. We need to interrupt the pulse generator's energy stream. I've adjusted your shield system so that it will deliver an EMP (Electro Magnetic Pulse) burst to disrupt the generator. You will need to walk into the beam, to trigger it. The EMP blast should neutralize the generator. But it will also drain your shields, and you will be vulnerable until they recharge."

After the generator is neutralized:

Pulse generator 3

Pulse Generator surrounded by Flood Combat Forms

  • Cortana: "Objective accomplished! The pulse generator has overloaded. Scanning... the generator's central core is offline. Well done."

After going back outside, to the canyon:

Breaking Stuff to Look Tough[]

  • Cortana: "The second pulse generator is located in the adjacent canyon. Move out, and I'll mark the target with a nav point when we get closer."

Once onto the bridge in the middle of this canyon:

  • Cortana: "Head through that door. That's the way to the next canyon."

Once in the canyon with the 2nd pulse generator in it:

  • Cortana: "OK. Let's take care of the next pulse generator."

If you continue on to toward the 3rd canyon, before destroying the 2nd pulse generator:

  • Cortana: "Wait! We haven't destroyed the pulse generator yet. Find a Banshee, and fly it up to the location marked by the nav point."

After you destroy the 2nd generator:

  • Cortana: "That did it! The pulse generator overloaded. One more to go."

Once outside again:

The Tunnels Below[]

  • Cortana: "I've located the Pillar of Autumn. She put down twelve-hundred kilometers up spin. Energy readings show her fusion reactors are still powered up. The systems on the Pillar of Autumn have fail safes that even I can't override, without authorization from the Captain. We'll need to find him or his neural implants, to start the fusion core detonation. One target remaining. Let's take care of the final pulse generator."

Once you reach the tunnel leading to the 3rd canyon:

  • Cortana: "That tunnel leads to the next section of the canyon. The final pulse generator we need to destroy is through there."

Once you enter the third canyon:

Final Run[]

The Chief fights through an armada of both Flood and Covenant with supporting vehicles. After you destroy the final generator

  • Cortana: "Final target neutralized. Let's get out of here."

{Original Cutscene} {Anniversary Cutscene}

  • Master Chief: "Let's find a ride, and get to the Captain."
  • Cortana: "No, that'll take too long."
  • Master Chief: "You have a better idea?"
  • Cortana: "There's a teleportation grid that runs throughout Halo. That's how the Monitor moves about so quickly. I learned how to tap into the grid when I was in the Control Center. Unfortunately, each jump requires a rather... consequential expenditure of energy."
  • Master Chief: "Something tells me I'm not gonna like this."
  • Cortana: "But I'm pretty sure I can take the needed energy from your suit without permanently damaging your shields. Needless to say, I think we should only try this once."
  • Master Chief: "Do it."

Master Chief is teleported away. Fades to black.

Level ends.


Icon Name Description Value
HTMCC AchievementArt It-Was-Inevitable It Was Inevitable Beat the par score on Two Betrayals. 10G
Leave It Where It LayHTMCC AchievementArt Leave-It-Where-It-Lay Leave It Where It Lay Complete Two Betrayals on Legendary difficulty without picking up a new weapon. 25G (CEA)

10G (MCC)

Look Out for the Little GuysHTMCC AchievementArt Look-Out-for-the-Little-Guys Look Out for the Little Guys Finish the level on Heroic difficulty or higher (CEA) or Legendary difficulty (MCC) without killing any Grunts 10G
HTMCC AchievementArt Memories Memories Activate Terminal 8 on Two Betrayals. 5G
HTMCC AchievementArt Skulltaker-Halo-CE-Pinata Skulltaker Halo: CE: Pinata Find and claim the Pinata skull in remastered mode. 5G
Two Betrayals (achievement)HTMCC AchievementArt Two-Betrayals Two Betrayals Complete Two Betrayals. 25G (CEA)

10G (MCC)

HTMCC AchievementArt Whistle-Stop-Tour Whistle Stop Tour Beat the par time on Two Betrayals. 10G


  • Some of Guilty Spark's dialogue in this level point to his rampancy. His assumption that Master Chief knows what Halo is and what it does as well as his line about a question posed to him previously points to the fact that he has confused Master Chief with a Forerunner.
  • This is the only level in the entire game which allows the player to use every weapon (not counting vehicles).
  • After you exit the last blast door of the control room, if the player heads up the 3 levels of the stairs of the spire, they will be rewarded with a hidden human ammunition cache consisting of 2 cases of shotgun ammunition, some human blood, a Sniper rifle with only 8 bullets, 5 cases of pistol ammunition, a pistol, and 4 fragmentation grenades.
  • The human bodies and weapons in the pit seen in the Assault on the Control Room (level) have disappeared. A plausible explanation is that the Flood reanimated the bodies. However, it is more likely to prevent the player from accessing large amounts of ammunition for power weapons like the rocket launcher too early into the level.
  • About halfway through the level, the player will come across a room where when they first open the door, the player will see a dead Ultra Elite and a dead Minor Grunt with Infection Forms on them. Sometimes the infection forms will just stare at the player and not attack. Strangely, when they don't attack, and if you shoot or melee one of the infection forms, all of them will pop.
  • If you take the Banshee to the control room and go around Halo's hologram you can see on one of the markings what seems to be the UNSC Pillar of Autumn. There seems to likely be another one since the Autumn landed first, said markings were used for every starship that landed like the Truth and Reconciliation that landed second.
  • The player can snipe the Wraith driver at the beginning of the level. When the music starts, aim at the Wraith and the player will see an Elite. This trick can help favorably in Legendary.
  • This level is similar to the Halo 2 level, Quarantine Zone as they take place at night in a snowy place, has the player fighting the Flood and Sentinels, involves the Index being stolen, and involves betrayals at the beginning or end of the level with someone who helps guide the player to the Index.
  • Some have wondered why Cortana says things like 'sod off' and 'toady about' in this cinematic. The reason for this is that apparently Jason Jones wanted Cortana to have a British accent originally. This was confirmed in the Halo 3 Legendary Edition disc. In addition, in Halo: The Flood, Cortana says 'piss off' rather than 'sod off'.
  • On rare occasions, the second blast door in the chasm will lock itself leaving players with no other option but to restart the level as a result of a glitch.
  • Despite the name "Two Betrayals," only one betrayal occurs: 343 Guilty Spark's turning against the Chief. Though it is possible that the Chief and 343 Guilty Spark can be looked at as betraying each other, or that it is referring first to Cortana 'betraying' the Chief by refusing to activate Halo, then to Guilty Spark.
  • This is the last level in which the player fights Jackals, and Zealot and Stealth elites in Halo: Combat Evolved.
  • After the player takes out the third generator, any remaining Sentinels in the room should die. However, in rare instances that the generator is destroyed and the Sentinels are left alive, they will begin attacking the Master Chief and, despite being in a scripted custom animation, his shields will fall and he will die. The dialogue continues regardless.
  • Halo Waypoint made a Vintage Fisticuffs video of what they call the "Grand Canyon." It' is the part where you must destroy the second Pulse Generator.
  • In Halo: The Flood, the Master Chief uses an assault rifle as his weapon in the beginning, switching to a Plasma Pistol later on.
  • In Halo: The Flood, a few dialogue changes are made to what is said in the beginning of the level.
  • Through the whole level, the player can notice that most of the trees and rocks from the earlier level (Assault on the Control Room) are not at the same places they used to be.
  • In the Halo CE Beta build 1749 and cut from release, the second pulse generator has an extra room before it, joined by the same connective hallway seen elsewhere in the level. The third/last pulse generator also featured an extra room first, with a short connecting elevator.
    • A fourth pulse generator exists but goes unused in the final release of the game, locked behind a closed door on the platform across the canyon from pulse generator two. The door is open in the Beta build, but for Release builds, mods or cheats can be used to clip through the closed door to enter this c40_b2 BSP which simply consists of a mirrored version of the beta 2-room design for pulse generator two. In both the beta and final release, no enemies will spawn, lighting is missing in the connecting corridor, and the pulse generator itself is inactive and not required to progress.[1] Otherwise, these rooms are fully textured and decorated, and in the H1A and MCC releases these rooms are surprisingly supported by the anniversary graphics.
      • In total, 4 extra rooms are found in Beta 1749 that were all cut by Release.