The book got an Updated Re-release in 2010, with several small details changed to make it mesh better with later canon. Elements from the novel would be used for the plot of the licensed arcade game Halo: Fireteam Raven.
Not to be confused with The Great Flood, although the allusion is intentional.
Tropes used in the novel:
- Adaptation Distillation: In the game, the Library level is one long and repetitive fight with a massive number of Flood enemies, limited ammunition availability, endless sets of identical-looking rooms, and 343 Guilty Spark yammering at the player the entire time to hurry up; not coincidentally, it is widely considered one of the worst levels in the entire Halo series. In the book? Less than one chapter.
- Adaptation Expansion:
- Ever wonder what the Marines were up to during the game? Now you know. Most of their time is spent recovering supplies and vehicles back from the Pillar of Autumn in large battles, taking prisoners, and trying to find another way offworld.
- The Elite (or one of the Elites) who ambushes you during "The Maw" was obsessed with killing you the entire time.
- Now you know how Keyes got captured by the Covenant and why his bridge crew from The Fall of Reach is completely absent after the first level.
- And I Must Scream: If you thought Jenkins' and Keyes' fates were bad, wait until they're given detail here. The Infection Form that got Jenkins was starved too long and didn't completely consume Jenkins' mind, leaving him free to witness himself killing and mutating and feeling the pain he takes from the mutations and gunfire, and Keyes has his memories - eventually his very personality - torn from him as the Proto-Gravemind tries to find Earth.
- Badass Normal: Sergeant Marvin Mobuto, who was Spark's first attempt to get someone to get through the Library. He managed to make it pretty far in before getting killed, and he wasn't a Spartan super-soldier, just a regular guy. The Chief makes it a point to show his respects to this soldier who he never met, precisely because he was able to survive that long in the Library.
- Beat Them at Their Own Game: What Silva hopes the ODSTs will accomplish by hijacking the Truth and Reconciliation, fulfilling the Pillar of Autumn's original mission instead of the Chief and his Spartans.
- Bittersweet Ending: To Wallace Jenkins's story; he's finally able to receive a Mercy Kill from McKay and dies thanking her.
- Bloodier and Gorier: The novel is much more graphic compared to the game it's based on with deaths and everything surrounding how being infected by the Flood works being described in detail.
- Butt-Monkey: Yayap. A Grunt who had the misfortune of encountering and surviving John, gets shackled with an overzealous idiot Elite, is beaten up and taken prisoner, and gets front-row seats to Halo exploding. And, of course, the Grunts as a whole.
- Characterization Marches On: This was one of the first Halo books ever put out, and the attitude of some of the Elites shows this. Zuka disobeys orders multiple times and behaves very much unlike the Proud Warrior Race Guy that the Elites would eventually turn out to be. One Elite even uses a human handgun to execute a human (though he immediately tosses it aside while contemptuously calling it 'primitive'), when later sources would retcon it so that Covenant-era Elites until the revelation of the Prophet's lies would willingly die with fully loaded weapons at their feet simply because they were "Unclean."
- Contrived Coincidence: Out of all the Flood forms McKay could have chosen to take prisoner, she decides to take the one inhabited by a half-living human desperately wanting to die. Similarly, the novel goes into great detail into why Jenkins kept some form of his mind after being assimilated - the Flood Infection form that hijacked him was too starved to make a complete override.
- Disproportionate Retribution: At one point, Ensign Dowski decides suggesting to Keyes to surrender to the Covenant, while being really insubordinate about it. Granted, this is one of the stupidest things anyone has said in Halo, but it's followed by Keyes tying her up and leaving her to be killed by the Covenant.
- Doomed by Canon/Downer Ending: As anyone who played through Combat Evolved would already know, the UNSC subplot ends with nearly all the humans dying on Halo; when Silva decides to bring a Flood-infested ship directly to Earth, McKay realizes that the Flood infection risk is far too great and chooses to sever the ship's controls instead, killing all hands on board.
- Fantastic Racism: Jackals hate Grunts, and abuse them at every opportunity.
- Fatal Family Photo: Played straight with Sam Marcus's picture of his wife. He doesn't even make it past the prologue.
- A Father to His Men: Major Silva and Captain Keyes.
- Fictional Document: The 2010 re-release to celebrate the launch of Halo: Reach includes a series of documents and transcriptions further expanding on the EU.
- Funetik Aksent: The Stealth Elite following the evacuating Pillar of Autumn's bridge crew has no idea who this "Keezz" person is, but he sounds important. He winds up getting headshot by "Keezz", who is, you guessed it, Keyes.
- Gender Bender: An ODST called Parker accompanies John on his mission to rescue Captain Keyes; they change from a he to a she between scenes. This was fixed in the 2010 edition, in which Parker is a male throughout.
- A Glass of Chianti: Major Silva jokes about the ODSTs not getting the wine in the officers' escape pods. Turns out, they actually have wine in them (Keyes is about to get some before noticing a cloaked Elite trying to kill him).
- Glory Hound: Major Silva very much wants glory for himself and his ODSTs. This ends up nearly getting the entire human race infected with the Flood when Silva tries to bring home a Covenant ship with Flood still on it, all just to gain himself and the ODSTs recognition and awards.
- I Die Free: Yayap the Grunt's storyline ends with him deserting the Covenant and fleeing in a Ghost with enough methane to survive on his own. It doesn't last long, but he actually finds a little bit of peace and quiet before the Pillar of Autumn's engines explode, even enjoying the warmth of the explosion.
- Irony: Yayap saves Zuka 'Zamamee's life during the assault on the Pillar of Autumn to give himself and his fellow Grunts an excuse to move away from the fighting. It just gets him transferred to a Spec-Ops unit which takes even more dangerous missions.
- Majorly Awesome: Silva is well respected amongst the ODSTs and is considered A Father to His Men.
- Mind Rape: After being infected by the Flood, Keyes is put through an absolutely excruciating ordeal as Gravemind literally tears his memory and personality apart in search for Earth's coordinates.
- Non-Indicative Title: The book's subtitle (The Flood) and cover art would make you think that it would be focused on the Flood. Instead, it's a novelization of all of the events that take place during Halo: Combat Evolved.
- One-Steve Limit: Averted with Ellen Dowski, the idiot who tries surrendering to the Covenant, and Ellen Marcus, Sam's wife. Given that the former is dead before the halfway point, and that the latter is The Ghost and never mentioned after the prologue, it's not too noticeable.
- The Only One Allowed to Defeat You: Zuka 'Zamamee, a Special Ops Elite who survived an encounter with John, tries his damndest to get approval to pursue and kill "the Demon". Not that John knows.
- Proud Warrior Race Guy:
- Zuka 'Zamamee. Even more so than other Elites (who are a race full of them). Even his superiors tell him to knock it off at times.
- The ODSTs, especially Major Silva, who hates John for killing four of his best men a few years back.
- Tellingly, this status gets both Zuka and Silva killed. 'Zamamee spends most of the plot trying to kill John, but ends up being fragged by the Chief without much of a fight. For his part, Major Silva nearly dooms the entire human race by attempting to bring a captured Flood-infected Covenant ship directly back to Earth in breach of the Cole Protocol, all just because he believed it'd bring him and the survivors (especially the ODSTs) fame and glory (a Covenant ship had never been captured before, and he believed it'd bring him and the survivors); if McKay hadn't stopped him, either the Covenant would have tracked them back to Earth, or the Flood would been well on their way to consuming the entire galaxy.
- Quintessential British Gentleman: Wellsey, the other AI aboard the Pillar of Autumn. Actually pretends to be the Duke of Wellington, down to his appearance, mannerisms, and insisting that he was there at his actual victories, which annoys his acquaintances.
- Remember the New Guy?: Applies to most of the cast, barring the Master Chief, Cortana, Keyes, Foehammer, Johnson's squad, the two techs from the first level, and the bridge crew members who had previously appeared in The Fall of Reach. That said, most of the newcomers either have all their scenes taking place in the offscreen portions of Combat Evolved, or are simply fill-ins for already existing Marine and Covenant NPCs, though the fill-in characters' actions don't always correspond with those of their in-game counterparts. However, there are still some glaringly straight examples:
- Though it's logical that the new Covenant and Marine characters wouldn't have had much, if any, chance to directly interact with Keyes in The Fall of Reach, the same cannot be said for bridge crew members Ellen Dowski and Gail Purdy, who were not mentioned at all in The Fall of Reach.
- Wellsley is a strange case; The Fall of Reach mentioned offhand that the Pillar of Autumn had two AIs assigned to it, but The Flood depicts him as escaping to Halo's surface with the ship's ODST contingent, even though Combat Evolved makes no mention of a second UNSC AI working with Cortana.
- The book claims that some of the Marine NPCs Chief fights alongside are actually ODSTs, though the game itself makes no mention of this. This was probably because Combat Evolved came out back when Bungie themselves weren't planning on ever putting ODSTs into the games.
- Zuka 'Zumamee is a Spec-Ops Elite, an enemy type which only shows up in the final three levels of the original game. However, the book has him already fighting the Chief in the very first level.
- Finally, the book indicates about 300 humans were still alive when the Chief set off to destroy Halo, in contrast to Combat Evolved implying that almost all of the remaining UNSC soldiers had already died by that point (since there was no mention of any humans surviving the Flood outbreak except Foehammer).
- Retcon:
- The first chapter mentions that Jackals were also boarding the Pillar Of Autumn, though the titular level in Combat Evolved only has Grunts and Elites.
- One of the Elites makes an exception to the Covenants' refusal to absolutely use human weapons by snapping up a pistol and executing Hikowa. Though said Elite immediately threw away the pistol after firing that one bullet because his finger was too large to fit comfortably in the trigger guard, contemptibly declaring it 'primitive'.
- More importantly, the 2010 rerelease changes a number of details to make the book mesh better with later canon, as well as to simply fix internal inconsistencies.
- Rewarded as a Traitor Deserves: The naive Ellen Dowski insists that the Autumn's bridge crew surrender to the Covenant and receive mercy rather than keep fighting and all be killed. When they abandon her so only she alone can surrender, she deliberately leaks their location to the Covenant when interrogated to prove she's right. However, after capturing the rest of the bridge crew the Elite in charge systematically kills them off. Ellen protests about this in shock, only for the Elite to kill her too.
- Screw This, I'm Outta Here: Yayap, after failing to talk Zuka out of his suicidal quest to kill "the demon" (John), finally gives up and steals a Ghost to find a way off Halo. Unfortunately, he gets first-row seats to the Pillar of Autumn detonating and blowing up Halo.
- Shower Scene: The Chief, of all people, gets one at Alpha Base in the original version of the book. It's played for a bit of character-building, as we learn that a two-minute hot shower is a genuine luxury for him.
- Sudden Downer Ending: McKay, Silva, and hundreds of other marines manage to take over the Truth and Reconciliation, and are about to leave Halo... when Silva decides to A) get off Halo ASAP instead of doing a full sweep of the ship when Jenkins can feel various Flood aboard (where one Flood pod can easily destroy all of Earth) and B) take the Flood samples with him, despite the warnings of Wellsley and McKay. Even worse, he doesn't plan on containing them before taking off, being convinced that his people can save that part for afterwards. This is probably because they were all Doomed by Canon anyways. The sad thing is, even if Silva had ordered a full decontamination before takeoff, this trope might have still applied anyways, given that they had almost no time left before the Autumn blew up and took Halo with it.
- Sudden Sequel Death Syndrome: Keyes' handpicked bridge crew from Halo: The Fall of Reach are unceremoniously shot in the face when a Covenant dropship gets the drop on their crashed lifepod.
- Too Dumb to Live: Ensign Dowski, who asks if they can surrender to the Covenant. Keep in mind that the events of this book take place near the very end of the Human-Covenant War, and the Covenant have shown themselves to be very eager to burn planets to glass for simply having a few humans on them. Twenty-seven years of knowing that this is the genocidal, single-minded foe that humanity faces... and she suggests surrender. This would be equal to an ice cube asking to surrender to the sun.
- Uncertain Doom: Like the game, the book ends with John and Cortana not being able to find any other survivors of Halo's destruction; the answer to whether these other survivors even exist is only revealed in Halo: First Strike.
- Unknown Rival: Zuka 'Zamamee to John, who is the nameless elite (or one of them) you kill during The Maw.
- What the Hell, Hero?: Wellsley sides with McKay in attempting to convince Silva to not bring live samples of the Flood back to Earth, condemning the colonel when he refuses to listen to reason:Wellsley: Then God help you, because if your plan fails, no one else will have the power to do so.
- Writers Cannot Do Math: On the opening page, no less. Sam Marcus is mentioned as getting his first sleep cycle in 36 hours; he'd most likely be useless at his job if was given a 36 hour shift, as it is insanely long. Even worse, it's mentioned he's only managed to get three hours of sleep since the Pillar of Autumn made a slipspace jump, which was twenty days ago. He's got three hours of sleep in twenty days, yet he's only portrayed as being a bit tired instead of, y'know, dead.
- You Are a Credit to Your Race: After Yayap successfully commands a team of Jackals in containing a Flood outbreak, he is promoted in their eyes to "honorary Jackal".
- Zombie Apocalypse: Courtesy of the Flood, a species of parasites who turn their victims into surprisingly intelligent (but no less vicious) zombies.
