The Library

From Halopedia, the Halo wiki

This article is about the campaign level. For other uses, see Library (disambiguation).


343 Guilty Spark


Two Betrayals

The Library
HCEA TheLibrary Loadscreen.png


Halo: Combat Evolved (Anniversary)

Map file name (?):





September 21, 2552


Inside the Library of Installation 04


Retrieve the Index.

Par Time:

00:25:00 (Master Chief Collection-only)

Par Score:

25,000 (Master Chief Collection-only)


Halopedia has a walkthrough guide for this level; see The Library/Walkthrough.

Fight your way through an ancient security facility in search of the Index.

The Library is the seventh campaign level in Halo: Combat Evolved. It begins after 343 Guilty Spark teleports John-117 from the swamp he was in to the Library of Installation 04. The Master Chief must battle through four Flood-filled levels to reach the Index chamber.


The Library[edit]

{Original Cutscene} {Anniversary Cutscene}

John-117 and 343 Guilty Spark teleport into the Library.

The view flies through the main central chamber of the Installation, through a rotating doorway, to find 343 Guilty Spark and the Master Chief teleporting in.

  • 343 Guilty Spark: "We must collect the Index before we can activate the installation."


Over the course of the level, 343 Guilty Spark mutters various phrases, which include:

  • "Doodeedooodooo..."
  • "Teeheeeheeeheeehee!"
  • "Huaaaaa, huaaaauuuuhummmmm."
  • "Ahhhh...I, am a genius. Heeheeheehee!"
  • "Hum hum huuuuum, hum hum hum."
  • "Ah."
  • "Oh. Hello."
  • "Hahahahaha!"
  • "Oh. That's a good idea."

If the Chief dies:

  • "Reclaimer, we must keep moving...! Reclaimer?"
  • "Oh, how unfortunate."
  • "Ah, a pity."
  • "I told you to upgrade to at least a class 12 Combat Skin!"

If the Chief attacks 343 Guilty Spark or the Sentinels:

  • "Please, stop being human."
  • "That is completely unnecessary."
  • "We have much more important business here."
  • "Please control your temper."
  • "Are you finished yet?"
  • "Please conserve your ammo."
  • "Please stop firing your weapon."

The Chief nears the Index Chamber

  • 343 Guilty Spark: "We are near the Index chamber. Follow me."

Spark flies over a wall separating a central chamber and the hallway the Chief is currently in. The Chief reaches, and goes through one of the rotating doors.

The Chief emerges into the large central chamber. Flood forms emerge behind the walls and approach the Chief.

  • 343 Guilty Spark: "The energy field above us contains the Index. We must get up there."

The Chief comes to a huge locked door.

  • 343 Guilty Spark: "The security doors have sealed automatically. I will go access the override to open them."

Spark flies through one of the tunnels. Flood forms assault the Chief. The Chiefs defends himself until Spark returns.

  • 343 Guilty Spark: "Please, follow closely. This portal is the first of ten."

If the player goes the wrong way.

  • 343 Guilty Spark: "That is not the correct direction, Reclaimer. If you do not follow me, you may become lost."

The Chief and Spark move into the next hallway. The Chief continues to fight the Flood.

  • 343 Guilty Spark: "Puzzling. You brought such ineffective weapons to combat the Flood, despite the containment protocols."

The Chief, under Spark's lead, fights through the facility.

  • 343 Guilty Spark: "The Flood must not escape the installation. They consume all."

They continue through the facility, going through another hallway.

  • 343 Guilty Spark: "You can see how the body has been transformed by the genetic restructuring of the Flood infection. The small creatures carry spores that cause a host to mutate. The mutated host then produces spores that can pass the Flood to others. It is insidious and elegant. As long as any hosts remain, the Flood is virulent."

The Chief fights through yet another hallway.

  • 343 Guilty Spark: "We must continue. This way please."

They go further down another hallway.

  • 343 Guilty Spark: "This installation's research facilities are most impressive! Perhaps we'll have time to see them later."

Spark sends a group of Aggressor Sentinels to assist the Chief.

  • 343 Guilty Spark: "These Sentinels will supplement your combat system. But I suggest you upgrade to at least a Class Twelve combat skin. Your current model only scans as a Class Two, which is ill-suited for this kind of work."

The Chief nears the first platform lift.

  • 343 Guilty Spark: "Pardon me. A plasma conduit breach in Section 5-5-2-4 has disrupted power flow to a gravity maintenance assembly. Repairs require my attention. I will return soon."

The Chief rides the first lift to the second floor.

Wait, It Gets Worse![edit]

They move a short distance down the first hall of the second floor.

  • 343 Guilty Spark: "Flood activity has caused a failure in a drone control subsystem. I must reset the backup unit. Please, continue on. I will rejoin you when I have completed my task."

The Monitor leaves temporarily, and soon returns to the Chief with the door open.

  • 343 Guilty Spark: "The Sentinels can use their weapons to manage the Flood only for a short time. Speed is of the essence."

The Chief encounters another large door.

  • 343 Guilty Spark: "Please wait here."

The Chief approaches another hallway on the second floor.

  • 343 Guilty Spark: "Your environment suit should serve you well when the Flood begins to alter the atmosphere. You are a good planner."

The Chief once again fights through another hallway.

  • 343 Guilty Spark: "The installation was well conceived. It is surely the only way to end the Flood threat."

The Chief finds and rides the second platform lift.

But I Don't Want to Ride the Elevator![edit]

The Chief goes into the first hallway of the third floor.

  • 343 Guilty Spark: "I would conjecture that the other species currently on the installation is responsible for releasing the Flood. They seem most persistent in their attempts to access restricted areas."

The Chief comes into another hallway, but this time it's large, open, cavernous.

  • 343 Guilty Spark: "Why naturally the Flood is simply too dangerous to release, and mass sterilization protocols may again need to be enacted. Of course, samples were kept here after the last catastrophic outbreak... for study. It seems... that decision may have been an error."

The Chief enters another hallway.

  • 343 Guilty Spark: "The installation was specifically built to study and contain the Flood. Their survival as a race was dependent upon it. I am grateful to see that some of them survived to reproduce."

The Chief reaches the third floor's locked door.

  • 343 Guilty Spark: "I will deactivate the security lock. Wait here."

Spark once again leaves and returns to the Master Chief.

The Chief moves into yet another hallway, but this time with slightly more Flood forms.

  • 343 Guilty Spark: "Please stay close. Time is short."

The Chief rides on the platform lift to the fourth floor.

Fourth Floor: Tools, Guns, Keys To Super Weapons[edit]

The Chief enters the first hallway of the fourth floor.

  • 343 Guilty Spark: "The Flood are already hard at work repairing your vessel. Its parasitic nature belies the Flood's intelligence."

The Chief clears the route to the Index platform, fending off several remaining Flood forms. He reaches the platform.

{Original Cutscene} {Anniversary Cutscene}

The platform moves down to the lowest floor.

  • 343 Guilty Spark: "The energy barrier surrounding the Index will deactivate when we reach the ground floor."

The platform's bottom ledges interlock with the ridges below, and it finally comes to a halt.

John-117 acquires the Index.
  • 343 Guilty Spark: "You may now retrieve the Index."

The Chief walks slowly over to the Index, which is held in a protective sheath. The sheath unlocks itself as its sections move outwards before the Index itself pops slightly out of the top of the sheath. The Chief removes it and stares at it for a moment before 343 Guilty Spark zaps it from the Chief's hands and into some sort of trans-dimensional storage chamber inside the Monitor's body.

  • 343 Guilty Spark: "Protocol requires that I take possession of the Index for transport. Your organic form renders you... vulnerable to infection. The Index must not fall into the hands of the Flood, before we reach the Control Room and activate the installation."

Spark and the Chief teleport away from the platform.

  • 343 Guilty Spark: "The Flood is spreading! We must hurry!"

Fades to black.

Level ends.


The following achievements can be unlocked on The Library across the Xbox 360 and Halo: The Master Chief Collection editions of Halo: Combat Evolved Anniversary. The original Xbox and PC and Macintosh releases of Halo: Combat Evolved did not contain achievement unlocks.

Halo: Combat Evolved Anniversary (Xbox 360) Halo: MCC (Xbox One, Xbox Series X|S) Halo: MCC (Steam) Title Unlock requirement Games
HCEA Achievement The Library.png
HTMCC HCEA Achievement The Library achievement art
Steam Achievement Icon for the Halo: The Master Chief Collection - Halo: Combat Evolved Anniversary achievement The Library
The Library
Complete The Library on any difficulty.
Halo: Combat Evolved Anniversary
Halo: The Master Chief Collection
HTMCC HCEA Achievement Close Quarters Combat / That Just Happened achievement art
Steam Achievement Icon for the Halo: The Master Chief Collection - Halo: Combat Evolved Anniversary achievement That Just Happened
That Just Happened
Complete the level The Library on Heroic difficulty or higher without dying.
Halo: Combat Evolved Anniversary
Halo: The Master Chief Collection
Speed Reader
Complete the level "The Library" on Legendary difficulty in 30 minutes or less.
Halo: Combat Evolved Anniversary
HTMCC HCEA Achievement TLDR achievement art
Steam Achievement Icon for the Halo: The Master Chief Collection - Halo: Combat Evolved Anniversary achievement TLDR
Beat the par time on The Library.
Halo: The Master Chief Collection
HTMCC HCEA Achievement Reading Room achievement art
Steam Achievement Icon for the Halo: The Master Chief Collection - Halo: Combat Evolved Anniversary achievement Reading Room
Reading Room
Beat the par score on The Library.
Halo: The Master Chief Collection
HTMCC HCEA Achievement Quis custodiet ipsos custodes? achievement art
Steam Achievement Icon for the Halo: The Master Chief Collection - Halo: Combat Evolved Anniversary achievement Quis custodiet ipsos custodes?
Quis custodiet ipsos custodes?
Find the Terminal on The Library.
Halo: The Master Chief Collection
HTMCC HCEA Achievement Skulltaker Halo: CE: Black Eye achievement art
Steam Achievement Icon for the Halo: The Master Chief Collection - Halo: Combat Evolved Anniversary achievement Skulltaker Halo: CE: Black Eye
Skulltaker Halo: CE: Black Eye
Find the Black Eye Skull on The Library.
Halo: The Master Chief Collection
HTMCC HCEA Achievement Skulltaker Halo: CE: Eye Patch achievement art
Steam Achievement Icon for the Halo: The Master Chief Collection - Halo: Combat Evolved Anniversary achievement Skulltaker Halo: CE: Eye Patch
Skulltaker Halo: CE: Eye Patch
Find the Eye Patch Skull on The Library.
Halo: The Master Chief Collection

Production notes[edit]

Main article: Development of Halo: Combat Evolved

The Library was primarily designed by Bungie designer Tyson Green. According to Tyson, the mission's design was inspired by the level "If I Had A Rocket Launcher, I'd Make Someone Pay" from Marathon, and the first part of the Marathon 2 level "Begging For Mercy Makes Me Angry!"; specifically to create a level that had a feeling of "It's just you, your shotgun, and a the need to keep on moving.".[1]

According to designer Jaime Griesemer, the initial level design was "a giant vault", that would have had the player descend a "corkscrewing" staircase, with the activation index hovering and pulsating in the center. Flood forms would be able to jump to the player from different levels. However, the design was ultimately changed due to performance reasons, with walls being added throughout the level to reduce the number of objects being rendered, no longer allowing players to use the index as a constant point of reference to gauge their progression in the level.[2]

According to Tyson Green, The Library was the first level to implement Flood forms, and served as prototype level they would be developed on. At that time, the only NPC AI present in the mission were the Elite Combat Form and Carrier Form. The bare and extremely repetitive nature of the mission during this time started discussions over possibly removing a floor, but the action was deemed unfeasible; and eventually these worries were eased as 343 Guilty Spark, the Sentinels, and other Flood forms came online.[1]

Art Director Marcus Lehto designed the blue plasma screens in the hallways, while Paul Russel designed the patterns on the elevator floors.[2]

The events of the level were later expanded in the novel Halo: The Flood. One of the dead human combat forms found on the third floor in the level was identified as Staff Sergeant Marvin Mobuto, who was brought to the Library by 343 Guilty Spark in an attempt to retrieve the index. Mobuto's body was described as mangled to the point where even the Flood could not make use of it.

The Library would become one of the most notorious levels in the Halo series. The length of the level has been criticized for being too long, and the layout was confusing and repetitive.[2][3] When reflecting on the level, lead designer Tyson Green had said "If I had to all to do again, I'm sure the level would be shorter, but no less difficult.".[1] In an attempt to help counter this, the Anniversary graphics made the colored lighting themes for each floor of the Library far more blatant and noticeable than before, to at least give the floors stronger visual distinctions.[4]

The layout of the Library was briefly reused for the Library of Installation 05 during the final section of the Halo 2 campaign level Quarantine Zone.



Main article: Glitches
  • If the player has an Overshield, it is possible to launch him/herself onto the Activation Index. The player can fall to the bottom of the place right below this post and survive.
  • On the second elevator ride, if the player get high enough, jump off and get under it, the player can make their way to the center of the chamber and jump into the pit. There a spinning Forerunner Monitor, 343 Guilty Spark, can be seen. Oddly enough, the player can also do this while 343 Guilty Spark is supposedly on another part of the level at the time.
  • If there are any Flood corpses on the elevator during the cutscene, the corpse will start bouncing and it will keep going all the way down to the bottom until the elevator stops.
  • In Halo: Combat Evolved Anniversary, there is an error in the geometry of the remastered graphics on the top floor, with the yellow lighting. One specific part of the floor features a dead-end corridor with a health pack with two pillars sticking up, a common sight in the level. But the remastered graphics in this instance places a flat wall texture across at the part of the corridor where the pillars begin. This means the player can walk between the pillars and through the "wall" into what appears to be empty space, where they can see behind the walls of the level.

Easter eggs[edit]

  • The Black Eye skull is located in a vent before entering the Index chamber for the first time. On the first floor at the beginning of the level, you will notice squarish openings in the ceiling that the flood use to enter the level. Before entering the round, yellow room, find the vent closest to that door and do a grenade jump into it. The skull will be waiting for you.
  • The seventh Terminal is located on the Library's third floor. You will eventually come to the index chamber - a large circular room, with the Index platform above it. Go either right or left and jump over the low barriers until you get to the opposite side. The terminal flashes yellow, and can be clearly seen across the chasm.
  • The Eye Patch skull is behind the Index on the final platform. Instead of running onto the platform to grab the Index, go around while remaining as far from the Index as possible. The skull will be waiting on the ground right behind it.


  • In the beginning cutscene, the container holding the Activation Index unlocks, revealing it for two seconds before the animation by what is seen appears to have restarted since the Index seems to disappear as if the container was never even opened. This might have been caused by a scripting error.
  • In the last cutscene, the Master Chief appears to stand on a transparent glass surface while retrieving the Activation Index. However nothing was really modeled and the Chief was standing on emptiness: it was a bug that Bungie forgot to fix. It was not fixed in Halo: Combat Evolved Anniversary.



  • In the Korean version of Halo: Combat Evolved, this level is named as "Finding the Index".[citation needed]
  • The blue-lighted windows seen throughout the level are rumored to be used to access the data archived by the Librarian although this has never been seen in any of the games thus far. In addition, they are described as "glowing blue monitors" in Halo: The Flood.
  • Opening this file in a modding program will reveal a Flood actor variant with a flamethrower. However no such Flood form spawns in the level due to the fact that in the Xbox version of the game the flamethrower was unfinished, even though the PC version of this level does contain a working flamethrower (which also doesn't have a spawn point as a random piece of weaponry lying around).
  • Whenever Sentinels are deployed to escort the Monitor, they only follow him until they reach certain landmarks such as the series of pillar-like braces occasionally found in the middle of corridors. There is a possibility that the braces are actually devices used to mark the areas where Sentinels which are permitted to occupy. Another theory could be that the braces found in areas serve as signs that the Sentinels found within the Library are not allowed to wander outside of certain perimeters.
  • In the Anniversary version of the level there is a small portion of the previously mentioned brace-like structures that can be broken off by means of grenade explosions.
  • Also in the Anniversary version, the decorations on the Library's walls resemble the monoliths/petals that surround the Portal at Voi.


Halo: Combat Evolved[edit]

Halo: Combat Evolved Anniversary[edit]


Preceded by
343 Guilty Spark
Halo Campaign Missions
The Library
Succeeded by
Two Betrayals