Not to be confused with a Holy Halo, although the parallels are intentional.Halo is a massive video game series and one of the premiere franchises exclusive to the Xbox. In the 26th century, Earth is at war with a powerful collective of alien races known as The Covenant, who share a fanatical religion and have declared humans a profane race to be wiped out. Bungie Studios created the game series and it has taken on a life of its own, with many Expanded Universe stories and other game genres. The first three FPS games form the main story with the main character, Master Chief, and his vital role in the war. There have also been several Novelizations, which forms the majority of the backstory, introducing and naming characters, events, and other information that fill in gaps in and between the games.The core of Halo gameplay revolves around the wrinkles it presents in the First-Person Shooter formula.
You can only carry two guns at a time; there is no Hyperspace Arsenal to speak of (although in the first two games, the weapon you didn't have equipped was invisible to other players). The guns all have different purposes and performance, so adapting your loadout to fit the situation is a smart idea. There's no Universal Ammo either: finding ammo for your assault rifle requires you to find another assault rifle. Blatant Item Placement is also averted; you can grab any weapons dropped by anyone, even the enemies, so you'll never run out of guns.
Vehicles are prevalent and are integrated seamlessly into gameplay: if you run across a jeep, or a hoverbike, or a tank, or even a Space Plane, you can jump right in and the game shifts instantly to a third-person perspective, with no Loading Screen or separate map or anything. Relatedly, many of the franchise's campaign levels are absoutely enormous, with some levels largely about driving from Point A to Point B while avoiding enemy fire. While it is possible to finish the level on foot (assuming there aren't any ramps to jump, high spots to get to or timed sections), it is in your best interest to use a vehicle whenever possible.
Movement speed is a lot slower than older games (comparatively, you move about half as fast as prior FPS heroes; the series didn't get a "sprint" function until Reach), partly to compensate for the inaccuracy of a joystick and partly for more "serious" gameplay. This is evident in how absolutely mandatory it is to pay attention to the Scenery Porn and navigate through any given location. You also have an extremely "floaty" jump, able to clear obstacles as tall as your character to facilitate some mild platforming.
The HUD built into your helmet includes a motion sensor to help prevent yourself from being shot in the back or reveal enemies just out of sight (although is only useful against moving enemies and at a certain range, making snipers more threatening). It also justifies the use of waypoints to direct your movement through a level and not getting lost trying to find the exit. Of course it keeps the standard weapons loadout and shield/health bar as well.
Customization features that vary wildly depending on the options presented in any given game. This ranges from Dual Wielding weapons to deployable tactical equipment to physical customization of the armor itself.
Of course, Bungie took advantage of these unique gameplay quirks to stage intense and frantic battles, increasing the emphasis on having the right guns, using all your attacks and knowing when to retreat and recharge your shields. As you can see, it's a gameplay style that is both twitchy and cerebral, with room for the guns-blazing approach and significant tactical depth. The style has been preserved, with only a few tweaks for the sequels (Dual Wielding, new or rebalanced weapons, new vehicles, some power-ups, etc) throughout the franchise... not to mention nearly every modern shooter game since. Its influence can be seen anywhere from Army Of Two and Gears of War (which spins the Regenerating Health and Take Cover aspects into a core mechanic) to Call of Duty and Left 4 Dead (two weapons, always-accessible melee) to... its own sequels, which, after Halo 3, deliberately stepped back to the style of the original.The plot is also fairly complex and alongside the gameplay sometimes requires you to engage in atypical combat. The music and voice acting are nothing to sneer at either. What has made the series so longlasting is the multiplayer component; starting with Halo 2, the game connected through Xbox Live and brought to Console FPS the kind of multiplayer experience which previously could rarely if ever be obtained without a computer.Halo is one of the best-known Killer Apps. When the original Xbox was announced, there was a lot of skepticism from those who had already experienced the Console Wars and had no reason to believe the Xbox would go anywhere. Their reasoning wasn't inaccurate: Three Is Death in the console market, which (until then) had had trouble supporting even two consoles; and, as released, the Xbox did not (seem to) have anything worth playing. (The fact the original Xbox was an American-made console didn't help, after the disaster the Atari Jaguar was.) But once gamers got their grubby little hands on it, Halo singlehandedly kept Microsoft in the race, with EdgeMagazine even going so far as to call it "the most important launch game for any console, ever." All of its sequels have set "biggest-opening-day" records. The franchise as of October 2012 is valued at a cool $3 billion.
Halo 2: Anniversary: An Updated Re-release marking the ten year anniversary of Halo 2, with updated graphics and bonus content. It will included with Halo: The Master Chief Collection, a compilation of the first four games starring the Chief that is set for release on November 11, 2014.
Halo 3, the conclusion of the original trilogy and the climax of the Covenant war.
Reach was Bungie's last Halo project, with Microsoft opening "343 Industries" to take up the task of managing the Halo franchise. There are also several novels and various other media that make up the Expanded Universe.
Halo: The Fall of Reach: A prequel to Combat Evolved and the book that spawned the expanded universe, written concurrently with the original game.
Halo: The Flood: A novelization of Combat Evolved which expands on the events on the first Halo ring.
I Love Bees: A Halo 2 viral marketing campaign which took place on an amateur beekeeper's personal website that had been taken over by AIs inadvertently sent back in time from 2552 all the way to 2004.
Iris: A Halo 3 viral marketing campaign which centered on the Forerunners.
Halo Television Series: Announced at E3 2013. Thus far, the only known detail is that Steven Spielberg will be producing it as an exclusive to the Xbox One.
Halo: Nightfall: A five part live-action series produced by Ridley Scott set for release in 2014, starring ONI agent Jameson Locke.
Red vs. Blue: A Fan Work that has since become a lucrative franchise in its own right, with Rooster Teeth being recruited by Bungie and 343i themselves to promote the newer games and reveal new features, as well as having Easter EggCameos in both Halo 3 and Halo 4. Grifball, the gametype they invented, was even made official, with its own icon, announcer line, and playlist.
The Forerunners themselves were originally tended to be this trope, but that was later retconned away.
Aerith and Bob: Not so much for any characters (the Covenant notwithstanding), but for UNSC ship names. The ones from the games are poetic and a little bit weird: Pillar of Autumn, Spirit of Fire, Aegis Fate, In Amber Clad, Forward Unto Dawn, and Say My Name. But ships from the novels tend to have (more) normal names like Leviathan, Fairweather, Gettysburg, Texas, and (eventually) Do You Feel Lucky?. The odd ship names are very likely a nod to Iain M. Banks's Culture universe and the shipnames of the Culture, a setting which also has giant ringworlds. This trope's prevalence in Halo really depends on the writer. For example, Halo: Evolutions had a story called "Midnight in the Heart of Midlothian" written by former Bungie staffer Frankie O'Connor, taking place in a ship called "The Heart of Midlothian."
A.I. Is a Crapshoot: There is an actual, In-Universe term for this- Rampancy. AIs in the Haloverse (at least those of human origin) generally have this happen about seven years into their lifetime, at which point they are usually destroyed.
A.K.A.-47: Sniper Rifle System 99D-S2 Anti-Matériel bears a heavy resemblance to the South African made NTW-20, manufactured by the Mechem division of the DENEL group, sharing many of the same features; chambering for the 14.5 x 114mm round, the stock, carrying handle/scope guard and the muzzle brake.
According to Robert McLees, the MA5B/C Assault rifle is NOT based off of the Belgian FN 2000, though he grudgingly admits that people would think that after comparing the two
"I don't know when the images of the FN F2000 appeared, but I didn't see them until three or four months after the game shipped, and I thought 'Oh great. Now everyone's going to think I swiped the design from Fabrique National.' It was surreal to see how close the Halo assault rifle was to its real-life counterpart... and it was all totally by accident."
—Robert McLees,Writer and Keeper of the Halo Story Bible
Aliens Are Bastards: Zigzagged with the Covenant. Though many of its members are shown to be absolute bastards to both humanity and each other, most of the Covenant isn't evil, they're just being manipulated, coerced, or enslaved by the Prophets (and even they're not completely evil). Even the Brutes, the most brutal and violent of the races, have some decent people. The Flood are evil, but there's an implication that the Gravemind genuinely thinks that it's doing the right thing by assimilating everyone (though The Forerunner Saga implies its true purpose is far more malevolent). By the time of the second game, a combination of the Prophets' backstabbing of the Elites and revelations about the Halos' true purpose causes many members of the Covenant to rebel and join with humanity.
Even the Covenant remnant, which still seek to wipe out humanity, somewhat avoids this; they're motivated by a mix of misguided religiosity and genuine concern about humanity's intent towards the rest of the galaxy, with its lesser members likely coerced into the whole venture.
Aliens in Cardiff: Thus far, the Covenant has not been mentioned as having invaded New York, Tokyo, L.A or any of the other usual cities. The Kenyan city of New Mombassa and Cleveland, on the other hand...
However, New Mombasa is treated as the future financial metropolis of the world, not as obscure as it is today. The Covenant were looking for a Forerunner artifact there too. Similarly, they Colonel Ackerson told them there was an artifact in Cleveland, so they would invade it and not destroy it; and hopefully his brother (who lived there) would be able to escape.
Aliens Speaking English: In the first game, you can sometimes hear the cowardly Grunts shout things like "he's everywhere!" and "run for your lives!" when you attack them. They're the only Covenant who speak English in that game, with the official explanation being that the UNSC hadn't quite finished translating the other Covenant languages yet.
In the other Bungie games (with the exception of Reach), the Brutes and Elites will also shout at you in English, presumably because the Mark-VI has updated translation software, due to Cortana accessing a Covenant lexicon aboard the Ascendent Justice.
And its powers, especially 7^3 (343), 7^4 (2401) and 7^6 (117649).
If you start counting at 0, like programmers do, the powers of 7 are 1,7,49,343,2401,etc. The 4th one is 343, the 5th is 2401. Which has a strong correlation with which Monitors live at which installations.
Artistic License - Astronomy: Harvest, one of the most remote Human colonies, and the site of first contact with the Covenant, orbits the star Epsilon Indi and is 12 light years away. Reach, the "Second Military Capital" of the UNSC, orbits the star Epsilon Eridani, at 10.5 light years away. Not only that, but it's closer to Harvest than it is to Earth. In addition, the UNSC has, by the time of First Contact, settled anywhere from 400 to 1200 other colony worlds, yet they had never encountered, say, the Kig-Yar, whose homeworld is only 35 light years away.
The Atoner: The Arbiter, though he grows out of it.
Ghost from Prototype
Mendicant Bias, after the Forerunner-Flood War.
Authority Equals Asskicking: Elite Zealots and Ultras > all lower ranks. The method of climbing the ranks for Elites is by kills; literally, the more enemies you kill, the higher up you go in ranks, and nothing else matters.
Some of the upper-level UNSC members, specifically Captain Jacob Keyes and Admiral Preston Cole. Especially Admiral Cole. The Cole Protocol, the in-universe biography The Impossible Life and Possible Death of Preston J. Cole, he will rock your shit.
Marvin Mobuto: What he does is so badass, the Master Chief himself says "I didn't know you, Sarge, but I sure as hell wish I had. You must have been one hard-core son of a bitch." In the book The Flood, halfway through the Library, Master Chief is almost overwhelmed by the huge numbers of Flood as he fights his way to the Index Room. Then, he finds the corpse of Sgt.Mobuto, a very normal Marine who was, in spite of his lack of Spartan training, energy shielding and so on used by the Master Chief, still managed to get within a few rooms of retrieving the Index.
Sgt. Forge He fights The Arbiter with a knife and wins. According to the Halo Wars timeline, he also gets into a brawl with one of the Spirits Spartan-IIs and appears to have held his own.) Those Spartan-IIs are the same ones who are able to defeat multiple Helljumpers unarmored. At the tender age of 14.
The Covenant, lead by the Prophet of Truth, is a religious, genocidal coalition of Scary Dogmatic Aliens bent on (unknowingly) causing intergalactic extermination by activating the Halo Array, as a means to "begin the Great Journey".
The Flood are a parasitic, mutated virus, represented by the Gravemind, that seek to literally feed on every organic species in the universe.
The Sentinels, spearheaded by their Monitors (i.e. 343 Guilty Spark), were created to contain the Flood, as well as anyone else that sought to prevent the firing of the Halo rings, and wished to steal the rings' activation indexes for their own purposes (the two go hand in hand).
In the first trilogy, whilst Humanity is fighting the Covenant in a decades-spanning war, both forces discover the Flood is a greater threat to life in the known galaxy.
From Halo 4, the Forerunners and their Prometheans (specifically the Didact) are seen as a greater threat.
By the last book of The Forerunner Saga, the Precursors are known to be the greatest threat to all life in the galaxy having progenated all other species and now wishing their ultimate subjugation and destruction as the Flood.
Biological Weapons Solve Everything: The first trilogy can be loosely interpreted to end this way. The eponymous Halos are installations which can wipe out all life within a certain radius, meant to "starve" The Flood. The Halos aren't biological weapons themselves, but they're clearly built to target certain forms of life (plants and most animals are left untouched, but anything sapient is toast).
The Prophet of Truth, on the other hand, seems like a definite Omnicidal Maniac in the games. However, in the books, his conversations and inner monologue make it clear that he believes that learning the truth about the Forerunners and the Halos would destroy the Covenant and bring about a deadly civil war. He was right.
The Forerunners genuinely wished to protect the galaxy and its inhabitants, but they grew complacent because of their extremely advanced technology, and when the Flood came knocking, they could only fulfill their duty as Guardians of the younger species of the galaxy by taking the Flood with themselves in a desperate last resort plan — which could be interpreted as a Heroic Sacrifice or the cost of their foolishness, depending on how idealistic/cynical one is.
While that is never explicitly said, there are many allusions to it, particularly after it becomes clear to it that it has lost:
Gravemind: Do I take life or give it? Who is victim, and who is foe?
Gravemind: Resignation is my virtue; like water I ebb, and flow. Defeat is simply the addition of time to a sentence I never deserved... but you imposed.
Boarding Pod: In Combat Evolved the Covenant attach these to the Autumn's lifeboat launch tubes and board through them. Seen again in 2 when the Prophet of Regret attacks Earth, sending pods to board and blow up three of the Super MAC stations guarding the planet. The Chief stops the destruction of one of them.
Book Ends: REACH CAMPAIGN SPOILERS AHOY. The first stage of Halo: Combat Evolved is the Pillar of Autumn. The final mission of Halo: Reach is also the Pillar of Autumn (not counting the Lone Wolf bonus mission). That being said, the final cutscene of Reach is also the first cutscene of Combat Evolved.
Master Chief's involvement in the games starts when he emerges out of a cryotube and shortly thereafter places Cortana in his helmet. His role ends when he removes Cortana from his helmet and enters a cryotube.
Broad Strokes: The games themselves are remaining internally consistent but the Expanded Universe has been set up for a great deal of rearrangement of facts and details. This is partly because the official canon policy is that when new material and old material conflict, the new material wins.
Cain and Abel: Mendicant Bias and Offensive Bias. Except it's Abel (Offensive) who defeats Cain, by leading him into a trap.
Capital Letters Are Magic: Standard formula for a Halo enemy, faction or MacGuffin; capitalise a regular English word. The Covenant, Halo, The Flood, The Librarian, The Index, The Arbiter, The Great Journey, The Ark, The Didact, The Composer...
Character Exaggeration: The Covenant's potential to "glass" entire planets is subject to a strong degree of exaggeration In-Universe. While they certainly have the capacity to reduce an entire planet's surface to glass using their energy weapons, it is a very lengthy process, and though impressive, is rarely worth the time it takes, leading the Covenant to focus on glassing major population centers and doing a few other token sweeps. With atmospheric convection, the destruction is equally deadly if less absolute. For their part, the Covenant boast of their ability to cleanse entire planets, while reports to the UNSC exaggerate the destructive potential to galvanize humanity into action. This is backed up by information from one of the datapads in Halo: Reach, saying that the Covenant do not have the resources to glass an entire planet and wage a multi-system war at the same time, and that to entirely glass Earth would require about thirty years of continuous bombardment by a fleet of equal size to that possessed by the UNSC.
Then again, said datapad was written only about a year into the war, when the Covenant were still only committing a relatively small percent of their fleet to the war effort; another datapad written around the fifth year of the war gives a conservative estimate of about one to over three centuries just to re-terraform four colony worlds.
Cool Ship: The Pillar of Autumn, In Amber Clad, Forward Unto Dawn, Truth and Reconcilliation, Shadow of Intent, Spirit of Fire from Halo Wars, and a slew of others from the novels. They also make A Good Name for a Rock Band. And then you have the funny variations for freighters: This End Up, Contents Under Pressure, Bulk Discount, Horn of Plenty, or Wholesale Price.
Humorously enough, there is an actual band called "Pillar of Autumn" that got their name from the ship.
Continuity Nod: Quite a few of them. Regret's carrier being able to jump inside Earth's atmosphere in Halo 2 is probably a nod towards the scene in First Strike in which Cortana discovers that this can be done by making the Ascendant Justice enter slipspace within a gas giant.
The Package has the Master Chief interact with Dr. Halsey face to face and she acts exactly like Cortana, right down to telling him "Don't make a promise to a girl if you know you can't keep it."
Continuity Drift: Halo canon has been experiencing this, though it's up in the air if some of the retcons are justified or not.
This mainly applies to the books, which by official policy are only canon if they do not contradict the games, even if the book comes out first. The most major game retcons were Johnson and the Arbiter surviving Halo: Combat Evolved, despite Cortana confirming everyone except Master Chief was dead at the end, which is justifiable given how important those two were through the rest of the game series.
Another notable retcon from the books is that in The Fall of Reach, Hunters are first encountered on Sigma Octanus in 2552, and the Elites were hypothesized but not confirmed until the battle of Reach. However, as mentioned in the Retcon entry below, other media showed that humanity had been fighting them since pretty much the beginning of the war; the 2010 reprint eliminates any mention of either species being newly encountered.
Corpse Land: Before you encounter The Flood, you'll come across areas filled with ravaged covenant corpses.
Cosmic Deadline: It's All There in the Manual, but the UNSC-Covenant war drags on from 2525 to 2552, with the campaign over Harvest alone taking at least six years. The UNSC is constantly said to be on the road to defeat from Day One, losing colony after colony to the Covenant for a full 27 years, with the Spartans being in active service basically the entire time. Everything hits the fan at a breakneck pace right at the end though, as within the span of July to December 2552 (just six months):
July 2552: Keyes becomes a captain at the Battle of Sigma Octanus.
December 2552: The Covenant loyalists try to take over the Ark. The Prophets get killed, the Gravemind and its forces get destroyed, and the war ends.
Crapsack Universe: "Welcome to the galaxy, mankind! Incidentally, our religion has decreed you to be a race of demons and we're going to genocide you now, no offense or anything. Oh, and don't mind the Gravemind over there, it hardly ever Mind Rapes anyone."
Oh by the way, think that before the Covies and Flood, it was nice? Nope! You live in a semi-authoritarian government with rebellion just about everywhere in the outer and inner colonies, and both sides are willing to use nukes should it be effective.
However it seems to be on its way to improving significantly now that the Prophets have been overthrown and the war is finally over. Time will tell if the peace remains intact though...
Crystal Spires and Togas - The Forerunner basically fit in this trope. There are crystals, sleek and ornamented structures, and lots and lots of spires. Their society model also fits in with this.
Dark Messiah: Covenant Prophets in general, particularly the Prophet of Truth (a blackmailer and generally ne'er-do-good).
Deflector Shields: Used extensively by The Covenant, and to a more limited extent by the UNSC after reverse-engineering The Covenant's shield technology.
Despotism Justifies the Means: The three high Prophets discovered that the humans are the rightful inheritors of the Forerunners legacy, and this would undo Prophets rule over the Covenant. So they set out to eliminate humanity to maintain their rule.
Determinator - The SPARTANs, especially the Master Chief.
By extension, the entire human race. We went from having an interstellar empire equivalent in size to the Covenant to nothing more than Earth and a few scattered colonies. We were still throwing literally everything we had at the covenant by the time they invaded earth. The Elites respected Humanity for its sheer determination and even before the civil war, wondered why we were never offered a chance to join the covenant. Not to mention that we had already dragged our way back from a complete dismantlement of our society and a partial devolution after engaging in a disastrous war with the Forerunners, which still took years ages to finish. The Humans kept fighting until the last man on their last world. And this was after successfully winning a war with The Flood.
Doomed Hometown - The colony of Reach. Also, the homeworld of every single SPARTAN-III.
Drop Pod - Human Entry Vehicles, the entire purpose of the ODST "Helljumpers." Elites are often dropped in similar Covenant pods.
Earth-Shattering Kaboom - What happened to Alpha Halo. And the Ark. And Alpha Halo's replacement. And the titular planet in Ghosts of Onyx: after nuclear warheads were set off in its core, it was revealed to be made of trillions of Sentinels. Forerunner worlds have a thing for getting blown up directly, or indirectly, by Spartans.
Also from Ghost Of Onyx, the so-called "Nova Bomb." (also a Chekhov's Gun since it was mentioned in an earlier novel, but didn't become a factor until a later book.) The bomb was accidentally set off aboard a Covenant ship in orbit of a planet and it proceeded to instantly vaporize an entire separatist fleet of hundreds of ships (which had been preparing to totally crush the brutes), shatter a nearby moon to pieces, and burn off the entire atmosphere of the planet below it as well as scorching the entire near side into a hellscape. The weapon in question was perhaps the size of a mini van... and Halopedia's calculations put the thing's likely megaton yield at 1.2 billion.
In Halo Wars, the crew of the UNSC Spirit of Fire destroys a Forerunner Shield World by overloading the ship's fusion core and sending it into its sun. The result is a Death Star-like explosion.
In Halo Evolutions, Admiral Cole fires a hundred nuclear warheads into the gas giant Viperidae's core, turning it into a momentary star and decimating the Covenant fleet. Also a case of No Kill Like Overkill and a possible Heroic Sacrifice.
While the glassing of the most human colonies doesn't technically count, it does render those planets uninhabitable.
More than that, Halo 2 and Halo 3: ODST take place during the same time. The fifth level in Halo 2 (Metropolis) ends with a Covenant ship directly above New Mombasa jumping into slipspace; the first level of ODST starts with that very event.
In The Fall of Reach he's described as having graying hair, and ghostly skin from wearing the armor all the time. Somehow, knowing that only makes him look more badass in-game.
For those interested, we actually do now have an image of John 117 without his armor several decades before the Halo trilogy begins thanks to the graphic novels: http://www.halopedian.com/John-117.
Additionally, the Halo 3 trailer Starry Night shows Master Chief as a kid, although his face is darkened by the night.
The opening sequence of Halo 4 shows the young Master Chief, presumably shortly after he "joined" the SPARTAN training. The freckled boy is sitting on his bed, arms wrapped around his knees, but you can still make out that the front of his shirt reads JOHN.
A face is visible under just the right conditions in Halo 3. But it's actually the face of Marcus Lehto, the Creative Art Director at Bungie. The inclusion of his face in the Halo 3 beta was an easter egg, he's known for many within the series.
The only image that Bungie has released thus far of an adult Master Chief without a helmet was their 2010 Christmas Card ◊ which shows the back of his head.
Averted eventually with the Halo 4 "Scanned" trailer, where the Chief is shown as a child, and as a teenager, in full clarity, up until the point when he first dons his MJOLNIR armor.
And at the end of Halo 4 on Legendary, his eyes are seen.
Fantastic Racism: All over the place; the Covenant in particular seems to have been deliberately designed so that each of its various species would be at each others' throats instead of the Prophets', with the hatreds lasting even after the collapse of the Covenant, with the Elites and Brutes in particular still waging massively destructive conflicts against each other. The Forerunners themselves, despite their ideology of being galactic guardians, treated other species in ways that were overly paternalistic at best, such as suppressing their client species' native technological development and showing absolutely no mercy to anyone who challenged their rule. Additionally, the Human-Covenant War had plenty of racial hatred in it, even outside of the whole "kill all humans" thing, with the slurs to match. Indeed, even after the Elites turn against the Covenant and end up allying with humanity, there are still a lot of bad feelings on both sides, with ONI actively attempting to sabotage the Elite leader most favorably disposed to humanity , and various Elite-led groups who are still trying to finish what the Covenant started.
However, one of the major plot threads in the second trilogy seems to be the Librarian's plans for humanity to become galactic caretakers who would actually be worthy of the title, and indeed, there are signs of increasing inter-species cooperation and toleration in general in the Halo 4 era; Spartan Ops mentions several ex-Covenant refugees have been granted asylum on Earth, a number of reasonably thriving worlds with mixed human and Covenant populations have cropped up post-war, and Escalation shows that the UNSC and the Arbiter's faction are still working quite closely together, with humanity even sending the Infinity to escort the latter during his peace negotiations with the Brutes (itself a step up from the absolute hatred his faction held for them five years earlier, despite the absolute failure of said negotiations).
Fantastic Rank System: The Covenant have a completely different rank system, with different ranks existing for different races.
Fantasy Counterpart Culture: The Covenant are a theocratic, imperialistic hegemony with a sword wielding warrior class. They name there weapons and vehicles with a Type-(Number) system. They fight a naval battle against Eaglelandish marines. Imperial Japan anyone?
A meta one in Halo 2. The game opens with Master Chief's bold defense of Earth. But the Covenant carrier flees and the second half of the game turns into a political plot playing as the Arbiter.
Halo 3: Master Chief and the UNSC break a hole through the Covenant's defenses so that they can deactivate the Ark artifact on Earth. The artifact turns out to not be the Ark, but a portal leading to the Ark, which is outside the Milky Way galaxy.
Halo 4: Master Chief and Cortana hurry to activate a satellite so that they can escape the abandoned planet they're trapped on and be rescued. The satellite turns out to be actually a containment pod of a Forerunner, who breaks free and resumes his genocidal campaign on humanity.
In Halo: Reach Dr. Halsey explains to NOBLE Team that on its current course humanity is doomed to extinction. The only solution lays in the Forerunner information she and Cortana have managed to decipher, explicitly calling it a Game Changer. This info reveals the location of Halo, and leads into the main trilogy, where the Covenant's resolve was broken when the Halo's true purpose was revealed.
Inverted with the previous events of the campaign. No matter what the UNSC tries to stop the Covenant on Reach, some new complication is revealed that just escalates the conflict. Destroyed their corvette attacking their base? Covenant Special Ops still got the data they were looking for. Infiltrated their radar dark zone? It turns out to be hiding an entire Covenant army. Destroyed their spire bases? Those turn out to be cloaking a Covenant super carrier. Destroy the super carrier? A fleet of hundreds more ships immediately arrive to take its place.
Hero Antagonist: Sesa 'Refumee's Heretics are disillusioned Grunts and Elites that found out the truth about Halo and formed a resistance movement against the Covenant, but remained an independent organization in their own right, centrally opposing the Covenant and attempting to sway more defectors to their cause.
Heroic Sacrifice - Sergeant John Forge in Halo Wars The books contain several good examples, as well.
The Arbiter tries to do this early in Halo 2, until Tartarus rescues him at the last minute. Whoever holds the title is typically sent on suicide missions anyway, so it's to be expected.
Spartan Kurt 051 does this in Ghosts of Onyx, setting off a FENRIS nuke to prevent the Covenant from accesssing the Shield World.
Cmdr Keyes almost sacrifices herself and Johnson to prevent activation of the rings, but Truth guns her down himself.
In First Strike, Vice Admiral Danforth Whitcomb and Lt. Harveson lured the entire Covenant fleet to the doomed Covenant StationUnyielding Hierophant. When it exploded, it destroyed over four hundred vessels, achieving one of the greatest UNSC military victories in the war, and delaying the invasion of Earth.
Thom-293, best known for the Deliver Hope trailer, who saved Kat's life by delivering the tac-nuke to the Covenant ship. Noble Six, the protagonist of Halo Reach, replaces him.
Carter: I'm not gonna lie to you, Lieutenant. You're stepping into some shoes the rest of the squad would rather leave unfilled.
In Halo: Reach, Jorge has a sacrifice when he manually detonates a "Slipspace bomb" to destroy a Covenant supercarrier. Carter has a sacrifice when he flies a Pelican into a Scarab to save Emile and Six. The player has a sacrifice when he stays behind on Reach to cover the Pillar of Autumn's escape, which he only has to do in the first place because Emile is killed just before attempting to do the same thing. Reach is basically made ofHeroic Sacrifice.
High Speed Hijack: Starting with Halo 2, enemies can hijack your vehicles in single-player, you can hijack theirs, and there's a medal for doing it to another player during a multiplayer game. SPARTAN-IIs can also hijack enemy vehicles in Halo Wars.
Hit-and-Run Tactics: You'll need these for dealing with Halo 2's final boss, even on Easy. Just take a look at what happens to your allies and decide if you want to repeat their performance.
In Halo in general it was best to use your rechargeable shields to pick off enemies one by one, retreating when under too much fire. This allows you to wittle down their numbers slowly rather than taking the whole squad on at once. Particularly important in the first Halo, where your health didn't recharge when your shields did.
Hivemind: Gravemind. Its computing power rivaled the entire Forerunner empire's data capabilities. You also have the Proto-Gravemind that's present on the Truth and Reconciliation with Keyes inside, as well as the Proto-Graveminds which serve as Flood bases in Halo Wars.
Holding Back the Phlebotinum: Why the UNSC does not field their emerging shield technology more widely. According to Dr. Halsey's diary that accompanies the Special Edition of Halo: Reach, humans have a very good understanding of shield technology now, but it is limited by two major related factors: size and power. As the volume of area to be shielded grows, the power requirements to maintain the shield increase exponentially. Shielding an entire starship would require several times more power than that ship can generate. However, shielding an infantryman or small vehicle has more modest power requirements, albiet still much more than an infantryman or small vehicle would typically have a power plant capable of producing. Humanity can make small enough power generators in the form of micro-fusion cells, but they are rarely cost-effective to produce, making each one almost the cost of a small starship. However, the SPARTAN-IIs already incorperate such a device into their Powered Armor by necessity, making adding shields to their existing systems relatively trivial. As for The Covenant technology they reverse-engineered their shields from? Humanity still has no idea how those things are powered, and from all appearances lack an obvious power source altogether.
Human Popsicle: The Cryo sleep tubes used by the UNSC during space travel
Humans Are Special - Hinted at strongly throughout the games, but ultimately confirmed in Cryptum. Humans were not actually related to the Forerunner, but were a seperate species that was active at the time of the Forerunner's war with the Flood. Humanity fought a war with the Forerunner because they were forced to expand and the Forerunner perceived this as a threat and the Forerunner won. Humanity had also managed to discover a means to destroy the Flood, but because they were fighting the Forerunner at the time, they refused to give them that information and destroyed it when it became apparent they were going to lose. The Forerunner took the few surviving humans and "degraded" them to Stone Age levels of technology to preserve the species while trying to figure out how they were able to defeat the Flood, but were ultimately forced to fire the Halo rings. Afterwards, the few surviving Forerunner concluded from their errors in judgment that humans may have been the better choice to serve as the caretakers of the galaxy, and set up their systems to recognize humans as Reclaimers for when they eventually returned to space.
Although, judging from Bornstellar and, to a lesser extent, the Didact, most Forerunners wouldn't give a crap if Humans were all vaporized by the military. It would seem that pre-Flood War era, the only Forerunner who did give a crap was the Librarian.
Humans Are Warriors - Many species of the Covenant believe it, especially the Sangheili, and the Gravemind believe that Humans are a greater threat to the Flood than the Covenant, who he only see as arrogant good-for-nothing fodder.
This Trope is explored in the Halo Legends episode Origins, remarking both the achievements that led humanity to be a growing civilization, and the unfathomable slaughter that war had caused upon them. After reviewing the story of both the Forerunners and Humanity, Cortana wonders whenever if warriors will ever be gone from the world... and, bitterly, she comes to the conclusion that they will never disappear, and that there would always be war.
It's Raining Men: The ODSTs , aka the Orbital Drop Shock Troopers, aka the Helljumpers.
And in Halo 3, MC falls two kilometers, lands on his back, and is pretty much only stunned. Apparently, he survived it, because he surfed through the sky on a door from the Forerunners ship.
Noble Six performs a similar act in Reach and survives a fall from orbit. However, a cutscene in the level preceding this occurrence shows that s/he is wearing a Reentry Pack and in the following level s/he is favouring his/her arm and starts on low health, making this a justified instance of the trope.
Jack of All Stats: Master Chief is this, as noted on the character page. In The Fall of Reach, Dr. Halsey notes that other SPARTANS are faster or stronger but Master Chief is the bravest and out of all of them (possibly in fact due to his wider and varied skill set and leadership skills) the best. According to Cortana, she chose him because he had something "the others didn't; luck. Was I wrong?"
Jerkass: Romeo, and O'Brian from The Package. He seems to regret it later though.
In universe, Brutes are given the derisive nickname "Baby Kongs" by UNSC forces, often just expressed as "Bravo Kilos".
Kinetic Weapons Are Just Better: 500 years into the future, we have AI, FTL ships, and Powered Armor, however, most of the UNSC's weapons and vehicles are just shinier versions of ours. Spartan Laser, MAC, and Gauss Cannon are exceptions of course.
Not a bad thing though, UNSC weapons tend to be more effective against the Flood than the Covenant's. Pure Forms on the other hand...
And energy weapons are more effective at draining energy shields.
Large and in Charge - The Gravemind, being a collection of thousands of corpses, is insanely big.
Large Ham - Truth and Gravemind are constantly contesting for the title. Sgt. Johnson and Rtas 'Vadum also do quite good jobs.
In fact, most (if not all) NPC Elites fit this as well. How, considering their bizarre mouths, are they able to so epically chew the scenery at times?
I HAD HIM! "COMMANDER, YOU FOOL!A THOUSAND HELLS AWAIT YOU!!!"
Elites aren't the surprising ones. SPARTAN-1337 manages to chew the scenery with a helmet on.
Lethal Joke Weapon: The Plasma Pistol and Needler, in a way. In a the hands of a Grunt or a Jackal (the most likely places to find them), they hardly do Scratch Damage except on the higher difficulties, but in the hands of a player the pistol alone has been the basis of several game-bending-if-not-breaking combos (such as the infamous Noob Combo of Plasma Pistol/Battle Rifle in Halo 2), and the Needler has the unique distinction of being the only Covenant weapon that is particularly effective against unshielded targets (at least until its ranged counterpart, the Needle Rifle, showed up in ''Halo: Reach;;).
You've got the (novels only) M99 Stanchion, a coilgun sniper rifle that fires a .21-caliber round at 15 km/sec, capable of reducing anyone the round hits to Ludicrous Gibs from over 4 kilometers out.
You've the ARC-920 Railgun in for infantry, which is powerful and accurate against enemies but poor against vehicles. Essentially a weaker Spartan Laser with no zoom.
You've got the M68 Gauss Cannon, mounted as turrets and on some Warthogs, firing a 25 by 130 mm slug at around 13.5 km/sec, useful for punching through tanks(or one-shotting infantry).
Then you've got the Magnetic Accelerator Cannon (MAC), the main weapon on UNSC ships, which fires a 600-ton shell at 30 km/sec, impacting with 64 kilotons per shot. It takes 3 shots to down a Covenant battlecruiser (likely more for the bigger carriers) and only one to put down a light cruiser or corvette.
Lastly you've got the Super MAC, found only as part of space stations in geosynchronous orbit over Reach and Earth. These suckers fire a 3000-ton slug at 12,000 km/sec; with an impact force of 51.6 gigatons per shot, they're strong enough to punch clean through any Covenant vessel, even the 27 kilometer long supercarriers, shields and all, blow a big-ass hole through the ship, and keep going with enough force left over to punch through (or at least deal extreme damage to) another ship.
Ms. Fanservice: Cortana. Probably also the reason that they dialed down Dr. Halsey's apparent age from 60 to 20 AT MOST in The Package.
Notably averted in the first game though, where she's remarkably "unsexy", almost butch at least compared to her later incarnations.
Motherly Scientist: Dr. Catherine Halsey was much of a mother figure towards the Spartan children while at the same time administering the augmentations that killed or permanently disabled most of them. Worthy of note, however, is that her motherly treatment of them when not subjecting them to painful augmentations is believed to be a major contributor to the emotional stability of the SPARTAN-IIs compared to the SPARTAN-IIIs.
No Campaign for the Wicked: Played straight for the most part in the story campaigns. For example, in Halo 2, you get to play a Covenant soldier, but you only get to fight heretical Covenant forces, or the Flood. You never get a mission where you have to kill humans, and killing any human allies (aside from fighting with player characters playing Master Chief) causes them to attack you if you do it too much. Otherwise the games are told from the human's POV.
No One Could Survive That - How did Johnson make it off of Halo 04? And in the third game, the Chief swan-dives off of Truth's Forerunner dreadnought from orbit, but is mostly unscathed.
The small crater where he landed includes a still glowing Forerunner door. Which he apparently used as a heat shield. Or surfing board.
In First Strike it is revealed that Johnson was able to escape on a Pelican with a few others. Concept art shows that the Chief rode on a door to slow his descent. He could survive the heat with his armor as some Spartans in Fall of Reach survive reentry when they jump out of their damaged Pelican.
Oh, Crap: The reaction of anyone, human or alien, after getting stuck with a plasma grenade.
To a lesser extent, the refit Pillar of Autumn, Capt. Jacob Keyes, commanding. Of course, we only see it in the books, but, still...
Noble Six too. Used to eliminate entire militia groups solo for a living.
The Only One: The Master Chief is one of a very small handful of surviving SPARTAN II Super Soldiers (and generally the only one available in his combat theater).
Given the Expanded Universe material, is getting less and less true. Originally, only 75 candidates were conscripted and out of those, only 33 made it to the front lines. Chief was supposed to be the last living SPARTAN-II test subjects alive after the fall of Reach. However, 22 have been confirmed to be alive or genuinely MIA (Spartans KIA are listed as MIA to preserve morale). So only a third of the original 33 fully functional Spartans are confirmed to actually be dead.
Oral Fixation: A pair, and actually quite prominent in the case of Sweet Williams Cigars. The brand is a favourite in the Halo Universe.
Captain Keyes and his pipe, especially in the books. Given UNSC No-Smoking regulations inside ships, Keyes chews the tip to calm himself.
Sergeant Major Avery Johnson, and his Sweet Williams Cigar. Chief Petty Officer Mendez in the books probably counts, too.
Posthumous Character: The entire species of Forerunners is this, with their artifacts being all that's left of them. Until Halo 4.
Powered Armor: The SPARTANs's MJOLNIR armor, as well as the armor worn by the Elites and Brutes (to a lesser degree). Rank and file Marines use powered exoskeletons to move heavy equipment, while the SPARTAN-IIIs wore semi-powered armor with a watered down version of active camouflage.
Privateer - Unlike the other Covenant races, the Kig-Yar (Jackals) are not officially a part of it. Instead, they're paid mercenaries who have to, at least, pretend to believe in the holiness of the Forerunners. They operate their own ships and are allowed to raid non-Covenant ships and colonies.
Deconstructed in the Halo Evolutions tale The Return. Years after the end of the Human-Covenant war, and after the Elites are victorious from the Covenant Civil War, the entire race (including the protagonist, a Shipmaster) faces a spiritual crisis. Without the Prophets to lead them, without the knowledge of forerunner technology, without knowing what would their gods want, and without a worthy enemy to fight, the Elites don't know what to do now that everything they believed in was a lie.
In this tale, the Brutes are also victims of the Deconstruction. The Brutes, after the deaths of their leaders, happily tinkered away with the equipment they were forbidden from using... but they were too savage, to the point the Brutes fought more among themselves than against the Elites.
The Sangheili, a.k.a. the elites, have been oficially recognized by the UNSC in Latin as "Macto Cognatus"as a species name, or literally "I glorify my kin.
Puny Earthlings (Played straight with the Elites, Brutes, Hunters, and most Flood forms. Averted when it comes to the Grunts, Jackals, and Drones.)
Rape as Drama: Strongly implied with the interactions between Cortana and Gravemind. Confirmed in the story Human Weakness in Halo Evolutions. This, along with making her live the experiences of individuals prior to being consumed by the Flood, and the Gravemind's constant breaking speeches that question not only her actions, but her very existence, drive Cortana to a tragically broken state by the time the Master Chief saves her.
On the level "Cortana", a message plays on the crashed pelican which draws about as close a parallell as possible, given that the victim isn't corporeal.
Cortana: I tried to stay hidden, but there was no escape! He cornered me, wrapped me tight... and brought me close...
RetconLots of them. The books, video games and other media frequently contradict each other on the dates of the timeline, the history of the Covenant and the level of technology that humanity has. Official policy is that games trump books, and new material trumps old material.
One particularly striking example was the incident involving Cortana, who opted to stay behind in High Charity in Halo 2 to detonate the crashed In Amber Clad's reactor to destroy said colony. The reason: it didn't have one of its own (not in-built, anyway). Then, in Halo 3, when Chief returns there to retrieve her, he is instructed to detonate the colony's nuclear reactor, which calls the validity of both a whole mission and a LARGE plot-point into question and could have been easily averted.
This is pretty easily explained. The entire reason Cortana wanted to detonate In Amber Clad's reactor is that she knew it would destroy Halo 05, NOT High Charity, which was always powered by the Forerunner Dreadnought within, meaning any reactor it had would never be enough to do the job. They detonated it in Halo 3 in order to stop the Gravemind locally and temporarily, then activated the incomplete replacement for Halo 04 to finish the job for good.
Some stories which takes place before the original Halo has neglected the fact that The Fall of Reach states that Spartan-IIs did not have energy shields until just before the Battle of Reach. In the case of Halo Wars, Ensemble has admitted that this was merely a gameplay decision and that, canonically, Red Team never actually had energy shields...until the Essential Visual Guide changed all that by simply saying that they were actually field-testing an early prototype.
The Package shows the UNSC ONI Prowlers having stealth field technology that puts the Elites' Active Camoflauge to shame, but in the novels they're just immune to sensors and painted black to hide in space. It also shows the Spartans dogfighting in space with ships that have energy shields, which should have been impossible due to when it takes place, see above.
The Fall of Reach originally claimed that humanity had never encountered the Elites until they attacked Reach...but they're encountered by the SPARTAN-IIIs of Beta Company during Operation: TORPEDO in Ghosts of Onyx, by the crew of the "Spirit of Fire" in Halo Wars, and by several SPARTAN-IIs and marines in Halo Legends, Halo: Evolutions, and The Cole Protocol, all of which took place long before the Battle of Reach. Finally, the 2010 re-release of The Fall of Reach eliminated any mention of the Elites being a newly encountered species, and the new "Adjunct" section outright showed several instances of direct Human-to-Elite contact taking place decades before the invasion of Reach.
Additionally, the events of First Strike was supposed to be the first time UNSC forces had ever engaged the Brutes, and then Contact Harvest, Halo Legends, Halo: Evolutions, and Halo: Reach all showed that they had been fighting each other since the beginning of the war. Once again, the 2010 re-release eliminated any reference to them being a newly encountered species.
Also, The Flood had Master Chief cutting and breaking the spinal cords of Hunters (supported by the fact that 1 pistol shot to the back would kill them), but Halo 2 would establish that they're actually giant colonies of worm-eel aliens with no central nervous system.
Although they do have spine-like bracers running up their backs in Reach.
Halo: Reach (and the journal that came with the Limited/Legendary editions) reveals that Halsey already figured out that there were other Spartan programs other than her own before the events of Ghosts of Onyx (though she's not aware of the true nature of the S-III program until said book).
Halo: Reach also shows the Pillar of Autumn in drydock during the battle (which never happens in The Fall of Reach, where it spends the entire fight up in space). Additionally, the game and Halsey's journal has it so that Cortana split herself before the battle, with the main fragment going with the Chief and the smaller piece staying with Halsey to translate a Forerunner artifact which would end up providing the main Cortana AI with the coordinates to Halo, seemingly invalidating the significance of the Sigma Octanus symbols from The Fall of Reach...unless the information from the Reach artifact was what allowed Cortana to translate the Sigma Octanus symbols in the first place.
Halo: Reach (see a theme here?) also extends the length of the titular battle from a single day to about a month. While the official explanation is that ONI kept the first stages of the battle secret, there are still some unresolved timeline discrepancies.
Rule of Symbolism - Halos, the Covenant, the Ark, John 117, the Flood, etc. It helps that these are their names translated into the closest English equivalent.
Salt the Earth: Taken to its logical extreme with glassing; the Covenant render entire planets barren. And it's a lengthy process, requiring multiple ships carrying out the bombardment from space after receiving approval from a Prophet.
Apparently, this is an exaggeration of scale. A full-scale glassing would require a lot of time and resources, including several Covenant fortress ships that would be otherwise better used elsewhere. Mostly, a glassing only turns the larger population centers and highways to glass, while large portions of untargeted area are burned out by convection (though even these lesser efforts are still effective in rendering the planet nigh-uninhabitable). It takes lots of time and effort (one data pad early in the war gave a conservative estimate of about one to over three centuries to just to re-terraform four worlds), but glassed planets can be rehabilitated, as in the case of Reach.
Sci-Fi Writers Have No Sense of Scale: The Halo Extended Universe is ridiculously bad about this. The novels cite insanely light masses for ships. The 480'ish meter long titanium armored frigate for instance is given a loaded mass of just 4,000 tons. Some rough math says that this results in a ship that's not quite lighter then air, which is about 1.2 kilos per cubic meter, but seeing as the frigate works out to something like 1.8 kilos per cubic meter it's damn close. It gets even more insane when we consider that the ship is supposed to be armed with a main gun that fires 600 ton slugs.
Then there's the SPARTAN-II armor, which supposedly weighs in at a metric ton, or 2200 pounds. A set of armor that weighs as much as a 2011 Chevy Camaro. In order for this to be true, it would need to be either much more bulky or made primarily of lead and gold. Plus, it's never explained how they don't sink into the ground when standing on one foot or destroy every ladder and staircase they ever use.
It's less glaring in more recent material from the expanded universe. Chief actually weighs in at about 1000 pounds in armor, the scaling of the UNSC fleet is justified in comparison to the Covenant's superior tech, and the weapon lore, MA Cs and plasma included, have been made reasonably realistic. Concessions to gameplay limitations aside, the technical stuff generally makes a surprising amount of sense lore-wise.
The population numbers given in the Halo 3 Bestiarum seems to be this for people who don't realize that they only refers to homeworld populations (hence why the number of Engineers is given only as "n/a", since they don't actually have a homeworld, not even an ersatz one like High Charity for the Prophets).
Don't forget Sergeant Stacker. He's that white Sergeant who fought through the Battle of Reach, Halo: Combat Evolved, Halo 2, and Halo 3. In Halo: CE, he gets rescued by Master Chief in the second level, attacks the Silent Cartographer alongside MC, helps MC destroy the power cores, then manages to somehow escape. He then fights in the Battle of Mombasa, leads the Marines to attack the Prophet of Regret, and gets captured alongside Johnson and Sergeant Banks. Their response is to break free and capture a Scarab, before returning to Earth. After all that, he then enters Voi and leads Marines to destroy an entire Covenant anti-air battalion. Finally, he gets deployed onto the Ark alongside the rest of the Marines and MC. When his unit is killed, his response is to organize an impromptu armored division, destroy a Covenant division and a Scarab, assault the Citadel, then escape off the Ark safely to return to Earth.
And that isn't where his story ends. He is also present in Halo 4, having, through some coincidence, been assigned to the Infinity for the very voyage in which they find the Master Chief, reprising his role as a tank commander from Halo 3.
Shout-Out - The Master Chief is John, Spartan #117 and is awakened from cryostasis at the start of the first game. The protagonist of Demolition Man is John Spartan, who was prisoner #117 of the cryogenic prison facility where he was kept for 40 years.
There are also several shout-outs to Marathon, the series' spiritual predecessor, and the Greek historical angle is carried over as well.
A lot of inspiration was taken from the Alien franchise, the Pelican drop ship is nearly identical to a ship with a similar purpose in Aliens.
Speaking of Aliens, look at Halo's Sarge. Then look at Apone from Aliens. Heck, look at the entire USCM from that movie and compare it to the UNSC from Halo.
Even better, in the first game you could find a bulletin board on the Pillar of Autumn. One of the signs on it is a lost pet sign for a cat named Jonesy.
A small one: in Halo Wars, the hero unit Spartan 42's real name is Douglas.
Space Marine: Both straight with Master Chief, and averted with the real space marines.
Although John's actually in the Navy. Rank of Master Chief Petty Officer. While not technically a Space Marine, he qualifies in other ways. This is also true of the other Spartans, being either commissioned (Lieutenant, Captain, etc.) or non-commissioned (Petty Officer 1st Class, Master Chief Petty Officer) officers, the Spartans are closer to Navy SEALS. The UNSC specifically trains a Marine Corps, and the more accurate Space Marine in the Halo series would be the ODS Ts; they have the armor, operate in space (their whole job is being dropped from orbit into battlefields) and work as a squad contrasting the often solitary operation of most Spartans.
Sparse List of Rules: The Cole Protocol is the UNSC's most important naval code, since it lists the actions they are not allowed to do to prevent the Covenant from discovering Earth. However several rules are often ignored because they're just technicalities. We only hear one of those, Subsection 7: "No captured Covenant vessel can be brought back to human space without a thorough search for tracking devices." (Useless because the Covenant self-destruct all their vessels in danger of capture. Or try to; John and his fellow SPARTANs manage to grab one in Halo: First Strike.)
Starfish Aliens - Engineers, Hunters (colonies of wormlike organisms in humanoid armor), Drones (insectoids with a Hive Mind), Flood Infection Forms, the Gravemind, and Flood Pure Forms.
The Starscream - Some hints in Halo 2, as well as most of the Expanded Universe stories since then have implied that Regret was this with regards to Truth.
This is confirmed in The Cole Protocol, when Regret realizes he'll be offed by the Prophet of Truth as soon as he finds no use for him, so he tries to get his own agenda fulfilled before Truth does. Then the Chief punched him to death, and Truth didn't bother helping his fellow Prophet.
Standard Sci-Fi Army: Naturally. Infantry dominate (from Light to Elite, and of course the Super Soldiers), although both sides use field aircraft and at least one Armored vehicle. Halo Wars expands on this, giving the UNSC Heavy and Elite infantry (the Hellbringers and Helljumpers respectively), APC's, and Anti-aircraft units. Several of the Covenant vehicles are effectively Technicals, being repurposed mining equipment.
State Sec: The Office of Naval Intelligence, they do some morally questionable actions for the sake of the UNSC's survival.
Suicide Mission: Occurs throughout the series, such as the Arbiter's first mission in Halo 2. The opening cinematic describes the ODST's mission to board the Covenant carrier while still in the air over New Mombosa as 'suicide mission'. And SPARTAN III's are expendable, intended to be sent on suicide missions.
Super Prototype: Inverted with the Arbiter armour, which has a cloaking system inferior to the modern Elite armour. Ditto with the novel Ghosts of Onyx- the SPARTAN III's had the inferior Semi-Powered Infiltration armour, which lacked the shielding and strength-enhancements of the MJOLNIR suits in favor of some camouflage ability. Played straight with the Master Chief's armor in the first and second games, however - it is markedly superior to the 'standard' MJOLNIR suit due to improvements in shielding and the AI support system that Cortana represents.
Master Chief himself, and by extension the SPARTAN-II's compared to the III's and IV's. In Halo 4 we get to see just how bigger he is.
Theme Naming: Not the characters, however. Until Halo Wars broke the pattern, all UNSC vehicles in the games smaller than a full-size spaceship were named after animals, while Covenant vehicles were named after spooks. Most of the small craft are still named/nicknamed after animals, while space fighters tend to be named after swords.
And even then Halo Wars only broke the pattern with the Shout-Out Cyclops and appropriately named Gremlin.
Covenant spacecraft names are generally religious allusions, such as the Truth and Reconciliation or the Long Night of Solace. UNSC ships are named based on importance to the plot - unimportant ships, if given a name at all, have perfunctory one-word names such as the Iroquois or the Savannah, while more important ones have poetic names like Pillar of Autumn or Forward Unto Dawn.
See also Meaningful Name, above.
Tron Lines: A common feature for Forerunner technology, especially weapons. Also some Covenant tech, appropriately.
Tykebomb: The SPARTANs began training when they were six.
Tragic Monster - Captain Keyes, mutated into a Flood "proto-Gravemind" form. MC puts Keyes out of his misery when he retrieves the neural implants.
Jenkins, too, in The Flood.
True Companions: Quite a few examples. Spartans (both Type-II and Type-III) are trained together from childhood and quickly become like family. Sangheili/Elites refer to each other as "brother" and are hardly ever seen without another of their kind nearby. And the squad in ODST becomes pretty tight-knit as the game's events progress, even though the opening cinematic establishes that each member of the squad is a replacement from another squad.
Spartans in general really, it's even said to be the "short definition of a Spartan."
After Halo 3: ODST it is now common knowledge that the ODSTs are held to just below the standard Spartans are; considering everything you have to fight in that game, without the Spartan's enhanced speed, jump, health, melee damage and life saving shields, it's a fair point to make that ODSTs get by on skill where the Spartans can survive just with their shields.
The Worm That Walks: Mgalekgolo/Hunters are a collection of worm/eel things called Lekgolo, combined to form a single entity with a single consciousness (single as in using "I, me, my" instead of "We, us, our").
You Are Number Six: True to a certain extent with all Spartans, who are given numeric designations. Typically they will retain their personal name, suffixing the numeric designation to this.
This trope is also literally true in Halo: Reach where the otherwise unnamed primary player character joins Noble Team as their new "number six."
Especially when you find out The Flood have already completely infected/destroyed at least one other galaxy already, before the Forerunner even encountered them at the edge of the Milky Way.
Apocalyptic Log: The Covenant is founded on one of these, except they thought it was holy writ.
Badass Boast: Nylund is particularly fond of these. Happens in First Strike (by VADM Whitcomb), Ghosts of Onyx (by Whitcomb again, through a recording) and The Impossible Life and the Possible Death of Preston J. Cole (by the title character), in all cases before the character who delivers the said boast destroys a large Covenant fleet.
Brain Uploading: Human Smart AIs are created this way. Dr. Halsey was smart enough to clone herself so she could create Cortana while keeping her own brain safely inside her skull where she needed it.
Actually, she only cloned her brain and had to make seven copies of it. Six of them didn't survive and the seventh one created Cortana. There's also a pretty good reference and allusion to Zeus and Athena too.
Colonel Badass: Colonel Ackerson somewhat as withstood interrogations by Brutes and still managed to protect Earth before being decapitated. It seems that Colonel Deen was he managed to break a Covenant Siege behind enemy lines.
Convection Schmonvection: Averted in the case of Covenant stategic glassing. Carefully placed Covenant warships in orbit rain beams of plasma down onto a planet's surface in a choreographed grid pattern. What does not die instantly from getting hit with the plasma will die somewhat less quickly from the convection as the atmosphere boils around them...
Creative Sterility: The Covenant, though technologically superior, are only so because they depend on weapons and ships salvaged from the ruins of the ancient Forerunner race, which they slavishly copy with religious reverence. Humans are the only species capable of innovation, and often incorporate and improve upon captured Covenant tech. The Master Chief's energy shields are based on the similar Elite model, for instance.
Though it's not so much that the Covenant are incapable of innovation as much as that they generally see even simply changing the settings on Forerunner technology as heretical. The Elites and the Prophets, for example, were already about as technologically advanced as 26th century humanity before they began messing around with Forerunner tech.
In Halo: Cryptum, the Prophets are noted to be a scientifically-gifted species whose technology equals that of their prehistoric human allies, who were nearly a match for the Forerunner themselves.
Darker and Edgier: The novels (particularly The Fall of Reach) are much darker than the games, almost to the point of being a deconstruction. They don't shy away from just how horrible fighting a war against an unstoppable alien juggernaught would be or how awful your life would be if you were a SPARTAN-II . They also portray the amount of damage that the human body can take much more realistically, with soldiers dying from a single plasma rifle shot, etc.
Especially the Halo: Evolutions short-stories. Dear God, don't read "The Mona Lisa" or "Stomping On the Heels of a Fuss" if you have a weak stomach. To elaborate, "Stomping" details Brutes treating prisoners like chew-toys, living in a complex surrounded by a field of corpses, and eating humans around a campfire like freakin' hotdogs, while "The Mona Lisa" is a graphic depiction of a Flood infestation. One Elite even stomps a human corpse into pulp simply to prevent it from being used by the Flood.
Does Not Know His Own Strength: The Spartans have trouble adjusting to their new strength right after the augmentation, to the point where John-117 thinks that the Artificial Gravity in the ship's gym is broken since he can lift the heaviest weights without effort.
Faster-Than-Light Travel: Slipstream space, which is more-or-less shortcutting through another dimension. One of the reasons for Covenant space superiority was their greater ability to emerge from Slipspace at pinpoint locations, whereas UNSC exit points might be inaccurate by as many as 100,000 kilometers.
Not only was the location more accurate, so was the timeframe. Travel time between stars didn't remain constant, and UNSC ships that departed at roughly the same time could arrive at their destination hours or even days apart, reason of which was not clear to the scientists but attributed to "eddies" in slipstream currents.
Foregone Conclusion: The title of the first book is Halo: The Fall of Reach. Guess what happens.
You know exactly what will happen in the Forerunner Trilogy.
Foreshadowing: Most famously, by Dr. Catherine Halsey in The Fall of Reach, when describing John-117:
"This child could be more useful to the UNSC than a fleet of destroyers, a thousand Junior Grade Lieutenants ? Or even me. In the end, that child may be the only thing that makes any difference."
Generation Xerox: Well, if you consider having your brain cloned and then used to create an AI as having an offspring, Dr. Halsey and Cortana definitely qualify. Particularly when we finally see Dr. Halsey in person in The Package—-she looks exactly like Cortana's hologram and says several of her lines word-for-word.
Hand Wave: Though there is a decent-enough explanation for why Sgt. Johnson was able to resist getting nommed by the Flood, it's never really explained how he, Lt. Haverson, Cpl. Locklear, and PO 2 Polaski were able to commandeer a Pelican despite being separated from other UNSC forces on Halo.
Heroic BSOD: Admiral Cole sure gets one when he fins out that his wife and the mother of his child, Lyra, is a high-level Insurrection operative.
Honor Before Reason: The Sangheili honor codes are well beyond the point of ridiculousness. Especially apparent in Halo: The Cole Protocol.
The various Human characters end up taking advantage of this.
Hope Spot/Diabolus ex Machina: In Ghosts of Onyx, Admiral Patterson is down to one carrier and three destroyers, facing two damaged Covenant destroyers. One is taken out, leaving a single Covenant ship utterly defenseless. And then a Covenant fleet 32 ships strong comes out of slipspace between the lone destroyer and the four UNSC ships, and promptly annihilates the human vessels.
I Did What I Had to Do: Haverson kills an Engineer who just repaired John's armor in order to keep the Covenant from getting any data on it. He finds the act just as despicable as Cortana does, but stands by his decision.
Jerkass: Antonio Silva hates the Spartans, especially the Master Chief due to John accidentally killing an ODST member a long time ago. Silva seems to have forgotten how this was a result of half a dozen of the best soldiers attacking a supposedly average fourteen year old.
The Last Dance: Admiral Preston Cole. After being depended upon for so long in the Human-Covenant War by the UNSC (compared in The Impossible Life and Possible Death of Preston Cole as being in command of the battles of the Alamo, Termopylae, Stalingrad, and Cold Harbor, and repeating them over, and over), it was believed that he began to fall under the psychological strain, to the point it was speculated that he fell into another Heroic BSOD... but one that led him to face three hundred Covenant ships around a gas giant, killing plenty of them with slingshot maneuvers, using gravity as both a lure and a shield against the Covenant Plasma shots, mocking them with a Bad Ass Boast that angers them and drives them towards him, and ending with an implosion using said goddamn gas giant into a sun, killing all three hundred Covenant ships.
"Listen to me, Covenant. I am Vice Admiral Preston J. Cole commanding the human flagship, Everest. You claim to be the holy and glorious inheritors of the universe? I spit on your so-called holiness. You dare judge us unfit? After I have personally sent more than three hundred of your vainglorious ships to hell? After kicking your collective butts off Harvest - not once - but twice? From where I sit, we are the worthy inheritors. You think otherwise, you can come and try to prove me wrong."
Lightning Bruiser: Kelly in the novels was always the fastest Spartan, even when they were children. Once she goes through augmentations, she's described as being so fast that nothing could touch her if she didn't allow them too. She can reliably reach speeds up to 62 KPH (roughly 38 miles an hour).
Of course, all the Spartans are Lightning Bruisers compared to normal humans.
Jorge-052, Noble Teams Heavy weapons specialist carries a massive Heavy Machine gun which would require an entire crew of regular humans to man and would probably be cumbersome in the hands of even the other Spartans. Jorge however doesn't seem to be slowed down by it in the slightest.
Macross Missile Massacre: UNSC ships of the line also carry ludicrous numbers of Archer missle pods that can produce this effect. Unfortunately they are not particularly effective against Covenant energy shielding. They are however very effective against unshielded Covenant ships.
MacGuffin: The Forerunner Crystal in First Strike.
A vehicular example is seen courtesy of the many starships in the series, especially the UNSC's vessels when confronted with the Covenant's plasma weapons. It is basically unheard of for a ship to come out of an engagement without being gutted within an inch of its life and/or requiring several months' stay in drydock to fix the myriad of meltdowns and decompressions. Apparently, all that armour and structure is like so much tissue paper.
The Covenant ships subvert this trope: while their shields are up, they are basically Made of Iron, and only MAC cannon rounds generally make a dent. Knock down the shields, though, and they can get blown apart with otherwise-useless Archer missiles.
And also averted for the Spartans — they repeatedly come back from injuries that would cripple or kill an ordinary human. Linda, in particular, came back to full fighting readiness after being clinically dead.
Meaningful Name / Ironic Nickname: The Prophet of Truch is a habitual liar and blackmailed the Prophet of Regret, The Prophet of Regret is impetuious and doesn't seem to regret his actions (except the ones the Prophet of Truth is blackmailing him for), and The Prophet of Mercy is completely merciless, to the point of psychopathy. According to Contact Harvest, Regret used to be the Vice Minister of Tranquility and was known for his confrontational attitude, and Truth got his later position after blackmailing the Prophet of Restraint over his illegitimate children. This sort of thing seems to be a Running Gag throughout the Halo universe.
Truth at least is intentional. He chose it to remind himself of his own lies and hypocrisy.
The name "John-117" also may have meaning; from biblical references (various passages in the Book of John or in Revelations with the numbers "1" and "7" could be read as relating to Halo's plot) to a Shout-Out to Demolition Man.
It's also often pronounced one-seventeen, 1:17 is 77 seconds and 7 is Bungie's Arc Number.
Naval Blockade: The UNSC blockaded the 26 Draconis System in an effort to keep FTL drive components from being shipped out, leading to an incident that sparked the Insurrection.
Necessary Drawback: The Spartan I training program was a mixture of Training from Hell and chemical enhancements but didn't result in a significant battlefield improvement. The Spartan II's had Training from Hell, chemical enhancements, cybernetic augmentation, and a custom-built Powered Armor but because of the high risk of deformities and death from the implants (low "graduation" numbers) it was deemed to not be cost efficient. Spartan III's (the subjects of Halo: Reach) were a balance between the previous programs to get higher numbers of Super Soldiers that could affect the tide of battle.
Nice Job Breaking It, Hero: During the fall of Reach, Admiral Whitcomb re-purposes one of the UNSC's new experimental NOVA Bombs and leaves it booby trapped so that if the Covenant took it back to one of their planets, it'd induce massive casualties. By the time the bomb detonates however, the Covenant is fractured under civil war and ending up annihilating a major reorganizing fleet of the faction that ended up siding with Humanity.
Though it is possible that if the fleet remained, they wouldn't have been desperate enough to side with the humans at all.
Also note that those Elites hadn't sided humanity, and were still hell bent on annihilating us.
If you consider O.N.I.heroes, their plot of fracturing the Elite society only created more forces who would take up The Didacts mission against humanity. And for causing Dr Halsey to side with them.
Taking one of the Spartans to train to fight the Insurrection actually causes some of the suspicious parents to become part of the Insurrection. Although that may be more of a source of irony...
Novelization: The first game has one, titled Halo: The Flood.
Reasonable Authority Figure: Haverson, despite outranking the Master Chief, willingly concedes command of the mission to the Spartan. Later when the mission changes and he retakes command, Haverson is still agrees to take them back to Reach even though he knows that Master Chief really only wants to go to check for surviving Spartans.
Remember When You Blew Up a Sun?: Or in the case of Admiral Cole, remember when you turned a gas giant into a sun and then it wiped out a hundreds-stong Covenant armada in a giant supernova?
As a real-life Out-of-Universe inversion of the trope, there is a painting inside an ONI base in Australia called Admiral Cole's Last Stand, described in Halo: First Strike. The book was published nearly five years prior to Halo Evolutions, but in-universe, it was ten years before the end of the war.
Taken to a whole new extreme with the infighting at the Office of Naval Intelligence. There the right hand doesn't even know the left even exists. Even more blatant when you consider the context behind this communication. To put it short, Ackerson kidnaps one of Halsey's Spartans(Kurt) to help start his own Mass Produced Spartan unit to compete with Halsey's. Kurt then covertly spirits a number of those Spartans from the S-III companies in order to form his own secret team of Elite Spartan III's outfitted with Mjolnir armor like the original Spartan II's. And everybody is in the dark about getting conned by somebody else.
The Rival: Spartans and ODST generally don't get along.
Rock Beats Laser: Used and/or subverted depending on certain circumstances. Human firearms can outperform Covenant energy weapons in some cases, such as against the Flood. Humans also tend to defeat the Covenant on ground battles. That said, in space combat the Covenant tend to have a massive advantage over the UNSC.
Sacrificial Planet: Most of the story takes place in late 2552, after the Covenant destroyed the planet Reach during their war against humanity. The Covenant had already burned 800 human colonies in the twenty-seven years of war before, but Reach, being humanity's second most important military stronghold after Earth, is viewed to be the point-of-no-return, the point where humanity has been dealt a crippling blow and needs to land a killing strike on the Covenant right away before they destroy Earth. The Fall of Reach is described in the first Halo book and playable in the prequel Halo: Reach, where you are Doomed by Canon.
Screw the Rules, I Make Them!: The Office of Naval Intelligence has a very complicated relationship with both civilian and military law. They have classified orders to ensure the Cole Protocol is carried out fully. It states that all navigational data must be destroyed upon contact with the Covenant, but that leaves a flaw. The navigational officer. ONI's exact orders are to "destroy all navigational data stored digitally or organically." They ignore the orders of anybody who could or would stop them.
Shotgun Wedding: Admiral Cole, twice. Subverted both times—- it looks at first like he's being forced to marry Inna Valkov, his first wife and an admiral's daughter but it turns out that he wasn't the father of her son. His second wife, Lyrra, is also pregnant when they get married which is too bad because she turns out to be a high-level Insurrection operative and the captain of the frigate that Cole has been hunting for years.
Space Is an Ocean: Averted, as the ships use the 3-dimensional, zero-gravity nature of space to their advantage, such as by flipping the Pillar of Autum 180 degrees in order to point the majority of their point-defense guns at the Covenant ships attacking their underside.
The Spartan Way: The training regimen of the SPARTANs as seen in the novels.
Super Soldier: The Spartans. You've been kidnapped by the army, kid, will never see your family again, and have been replaced by a clone that will die soon. You will have to go through grueling training and risky augmentation, then get stuffed into a suit of armour that makes people wonder if you're actually a robot, and have difficulty bonding with anyone not a SPARTAN II. Oh, and no one will ever know your real name, if you die you're listed as "MIA" or "WIA", and you no longer have any sex drive whatsoever. Who wants to volunteer?
Super Toughness: The Spartan II's. Less so with the Spartan III's, who were elite cannon fodder with the less powerful SPI armor.
Tempting Fate: Guess who kicks the crap out of Master Chief & Co. after the following statement:
Cortana: "Also, be advised, Chief, that there are ceremonial guards in this temple - a race we have not encountered before. Roughly translated from Covenant dialects, they are called 'Brutes.' They shouldn't be a significant threat or they would have been used in previous military situations."
Three-Laws Compliant: Mentioned by name. The default setting of the AI constructs. Disabled for normal military use, since the laws would force the AI's to prevent soldiers from sacrificing or even risking their lives in war.
Time-Delayed Death: In Ghosts of Onyx, Dante, after a particularly hectic firefight, offhandedly mentions "I think they got me." He then drops dead. Upon closer inspection, it turns out that nearly half of his torso had been blown off or melted, and he didn't even notice.
Tsundere: Sif in Contact Harvest is a textbook version.
Tykebomb: The Spartans were drafted/kidnapped when they were six years old, and due to their training were better fighters than most adults. Then they got augmented.
Theme Naming: This series and Marathon are part of one. Durandal, Cortana... Here's betting their next series will have a character named Joyeuse in it.
The War of Earthly Aggression: In the expanded universe, pre-contact with the Covenant, and continuing through the war, there was a huge ongoing rebellion movement in the Outer Colonies.
Outgrown Such Silly Superstitions: Subverted. Dr. Halsey is specifically stated to be an atheist, suggesting this distinguishes her in some way from other human characters. This is later confirmed in ODST with the character of Dutch, who is noted to be a deeply spiritual man and a student of religion and philosophy.
Wham Episode: Halo: Cryptum, SO MUCH. You were wondering how humans and Forerunners first met 100,000 years ago? How about... humans had an interstellar empire so large that it rivaled the Forerunners', until it was destroyed by the Forerunners for infringing on their territory while running away from the Flood, which humanity eventually defeated before falling themselves. That's right, ancient humanity were the first to find and fight the Flood (with the help of the Prophets). We even invented a cure for the Flood that DIDN'T involve the total annihilation of life in the galaxy, but it was destroyed (either out of human bitterness or Forerunner ignorance) when the Forerunners invaded, DEVOLVED OUR SPECIES and erased all traces of the earlier civilization, restricting us to our homeworld. The Librarian mentioned in Halo 3 was actually intended to keep us in check.
Wham Line: Again, the Forerunner Saga is full of these. Often mentioned offhandedly, as, at the time, they are commonly known facts that seem to have no relevance. A big one is offhandedly mentioning that humanity and the Forerunners were at war at one point, after which the Forerunner victors de-evolved us and confined us to earth.
About every time we learn something new about the Precursors, it turns out to be this.
You Gotta Have Blue Hair: One of the female Spartans (it was Kelly) is mentioned to have dyed her hair blue in The Fall of Reach, though by the end of the book it's gone back to its natural color.
Cortana and Serina both have blue hair (and blue everything else).
The All-Seeing A.I.: Noteably averted, in all games including the first Halo: Combat Evolved; Enemies are only aware of your last known position once they lose sight of you, so it's possible to flank and sneak up behind them in a firefight if you use walls as cover. One of the skulls in Halo 2 makes the game harder by making enemies aware of your position at all times.
Almighty Janitor: Subverted and played straight with the Rookie. After learning he fought his way through war-torn Mombasa by himself for several hours, Dare thinks he's one of these. The truth is he was knocked out in his pod for most of it. However, it's perfectly possible to confirm her suspiciouns through gameplay. Heck, if you get all the audiologs, a cutscene changes so Rookie knows more about what's going on than Dare does! And Dare's the intelligence officer!
Ascended Meme: In ODST, the location that played the Siege Of Madrigal also had a short, looping animation of Marty O'Donnell dancing and little winged hearts flying everywhere. The heart effect is available as a purchasable "dying armor effect" (like Grunt Birthday Party confetti) in Reach.
Attempted Rape: Commissioner Kinsler attempts to rape Sadie in the Audio Files' story. He tries and fails three times, and the third failure gets him brutally torn to shreds by an angry mob that he had his men fire on.
In the second game, an instrumental version of "Blow Me Away" plays when the Master Chief enters the Mausoleum of the Arbiter, where the Enemy Civil War is at its most epic. Cue the urge to kick ass and Chew Bubblegum.
Cortana even tells you it'd be better to sit this one out and wait for the enemies to kill each other. But with this music it's just impossible to do.
And not to mention that the second and third games had Steve Vai shredding over the more intense themes.
And then ODST pretty much blows everything that has come before away with a little thing called Air Traffic Control: imagine that playing while fighting against hordes of Covenant air support hundreds of feet in the air on the edge of a skyscraper.
Kinsler, the New Mombasa police commissioner featured in Sadie's Story, is a rephrehensible jackass, who is willing to sacrifice the safety of the citizens in his bid for payback as the city falls apart.
According to his profile, Noble Team member Emile-239 seem to fit this rather well, apparently so brutal that his superiors are reluctant to field him against anything but aliens, for fear of his brutality giving the media real "excess" to comment on.
In at least one section of the game, we're told "He says he wants to win the war, but he really just wants the enemy to die."
Badass: The Master Chief. Also, the entire race of Elites, basically bipedal, evolved Land Sharks with energy shields.
An oft-overlooked example is the Australian MarinePrivate Chips Dubbo featured in all the Bungie Halo games, who gets some of the most badass lines in the entire series.
Private Chips Dubbo: S'alright, I'd hide from me too!
And, of course, scar-faced, shotgun-wielding Sergeant Pete Stacker, who along with Dubbo is one of the only human characters to have survived all three games.
Badass Back: Aka Cheating Bastard Back, the Jackal snipers. In games 2 and 3 the Hunters can melee you behind their back too, which is instant death on Legendary.
Badass Boast: After being told that a message from the covenant keeps repeating, over and over, the word "Regret":
Johnson:: Dear Humanity, we Regret being alien bastards! We Regret coming to Earth! And we most definitely Regret that the Corps just blew up our raggedy-ass fleet!
The Heretic Leader in the same game speaks to the Arbiter and accompanying strike team through a hologram. It's short, but it implies a lot.
Half-Jaw: Come out, so we may kill you! Heretic: Heheheh... Get in line.
Bash Brothers: Hunters always come in pairs of two. In most games, they're identical and equipped identically.
The Battlestar: Any ship that figures into the main plot, such as the Pillar of Autumn, the In Amber Clad, or the Forward Unto Dawn. In Halo 3, the Separatist vessel Shadow of Intent takes the place of the Rebel Basestar. In Halo 4, we get the massive Infinity, which was originally constructed to be a last bastion of humanity should Earth fall, and is capable of launching entire flotillas of frigates from its internal bays.
The Mantle's Approach puts all other ships seen so far to utter and complete shame, being the former flagship for the greatest navy ever built. It's so large it needs its own teleportation grid, being 230 miles at its longest, and it's crewed by a total of one man.
Beating A Dead Player: The infamous teabag in multiplayer. Additionally, campaign NPCs and enemies will occasionally shoot enemy corpses (including yours) and shout at them.
During gameplay, Marines will occasionally shout "Get up, so I can kill you again", showing that this trope is in full force even In-Universe. It becomes slightly less funny when the Flood actuallydoget back up.
Beehive Barrier: The Bubble Shield. Back again in Reach with a healing ability.
Berserk Button. Don't try to destroy the Halo ring in front of 343 Guilty Spark. Just ask Sgt. Johnson.
Or kill a Hunter in front of its partner.
Big Damn Heroes: Happens quite a lot during cutscenes, and sometimes you can do it yourself.
In Halo 3, when Johnson is beaten up to make him activate the rings, you have a good view of the large window behind Truth, with a small dropship growing larger in the distance.
Bilingual Bonus: Regret refers to the Halo pulse as a "divine wind" in his sermon in Halo 2. In Japanese divine wind is kamikaze. Considering that the activation of the Halo array is essentially a suicide attack... Well, he was more on the money than he knew.
Bittersweet Ending: To the original trilogy; both humanity and the Covenant races have been badly mauled by their war, with most human colonies destroyed and billions of its people dead. Earth's defenses were badly mauled and many of its cities razed. The upside is that the war ends with the Covenant races freed from the Prophets' rule and humanity avoiding extinction and making peace with their former adversaries (with hope for future friendship), not to mention our heroes stopping the Flood from retaking the galaxy. The Chief and Cortana are presumed dead, but are actually floating in space in the back half of the Dawn, with no way to get home.
The Needler also counts. It would be virtually useless, despite the homing feature of the needles, except for the fact that once a target has enough needles in them, they simultaneously explode. So the needler can be useful, assuming a player can get enough needles in an opponent to cause the explosion.
Also, the Spartan Laser.
Reach adds the Plasma Launcher, which charges to fire more grenades, as well as an artillery target painter.
So much so that it took three whole games, and traveling over 250,000 Light years to actually get to using it.
"I'm a thief... but I keep what I steal."
The Halos themselves. If a Galaxy destroying superweapon is found in the first game it will be fired by the end of the third game.
Cliff Hanger: The first game ended with plenty of more story to tell, but still self-contained. Halo 2 has merely a pause in the story.
The Computer Is a Cheating Bastard: On Legendary difficulty, most notably in the second game. Rapid-fire plasma pistols, faster-shooting plasma rifles, insta-death melees, Badass Back sniper shots, attacks that allies and enemies can survive but are instantly fatal to the player (Two words: Beam Rifle), unfair vehicle damage allocation, X-ray vision, sniper-accurate grenade throws, stupid friendly AI, etc.
In the original game, the last level is the first level backwards. The second-to-last level is the second level with different textures. The third level is one half going in, one half going out. The levels after the library are the same as the ones before the library. Except, well, backwards.
Also, these are noticeable:
The LibraryEvery interior level in the original game.
The multiplayer map Death Island from the original game is essentially a remake of the level The Silent Cartographer. All they did was replace the override with 1 base and the map room with another...
The Level Floodgate in Halo 3 is pretty much the previous level, backwards. Except everything's apocalyptic, and the Covenant is replaced with the Flood.
There's also a slight subversion of this trope in the very end of Halo 3. The control room to fire the Halo is almost identical to the one in the first game, hinting that all Halos are merely copies of each other.
Although, since this Halo is an exact replica of the one from the first game, it's not that much of a stretch.
Oh yeah, the collapsing structure that you are driving through? It's the framework for that same island◊ from Silent Cartographer.
Reach does this in the opposite way you'd expect: the multiplayer maps were designed first, and then tweaked to appear in the campaign.
Also in Reach, the campaign level "The Package"'s first half takes place in the same area as the previous level "ONI Sword Base", except it's set at night, all apocalyptic, partially-flooded, you have a Scorpion to make the outside areas go by faster, and the elevator is out indoors so you have to use maintainence tunnels.
Cosmetic Award: The multiplayer armor permutations in Halo 3. Reach takes it a step further by forcing you to purchase them with in-game "cR". The prices are...Extortionate.
Cosmetically Different Sides: Elites and Spartans (though quite possible on the same team) are the same aside from visually in the multiplayer. Reach is supposed to be avert the trope, making the Elites take more damage and have an ability to roll, while the Spartans have the ability to sprint and are smaller targets.
Although the different body shapes between humans and Sangheili mean that scoring headshots on each is different, and there are some other profile-related differences.
Darker and Edgier: Halo 3 is the darkest of the original trilogy, the first two games largely avoided the implications of just how many had died/were dying in the Covenant War, but this game has Earth After the End and takes an Anyone Can Die approach to the main characters.
Halo Reach feels more like a war movie, with Reach falling and almost all of Noble Team dying.
Decoy Protagonist: The Rookie. If anything, Halo 3: ODST is the story of Buck, Dare, and the Superintendent/Virgil.
..unless you get all the audio logs, which makes you the one who knows more about the story than Dare, the Intelligence Officer, and you also get access to a bazillion guns in secret caches all over the city, thus making you a One-Man ArmyHeroic Mime who really wants to get back to sleep.
Halo: Reach implies that Noble Six was this to Master Chief in the series as a whole. Considering that Noble Six is completely customizable and is stated to have the same combat rating as Master Chief, this makes it one of the more sadistic examples.
Deflector Shields: Used by Elites, some Brutes, and Tartarus, whose shield can only be taken out with a Beam Rifle.
In Halo: Reach, there is an armor ability that lets you, temporarily, have unbreakable shields. As soon as the shields run out, however...
Enemy Civil War - The Covenant Civil War in Halo 2: Elites, Hunters and Grunts versus Brutes, Jackals and Drones. Beforehand, there was the Heretic uprising, with Spec-Ops Grunts, Elites and the Arbiter eradicating the defectee Grunts and Elites.
Enemy Mine - This quickly becomes a theme. The Elites join with the humans during the Covenant Civil War. Guilty Spark assists Master Chief after the destruction of his station. Even Gravemind lends a tentacle in his debut and again to stop Truth. Of course, some of these alliances are more lasting then others...
Escort Mission - The final parts of ODST have you, Buck, and Dare escorting the alien Engineer who's absorbed the Superintendent's data out of the data center, along a highway while it's inside a near-indestructible garbage truck, and finally defending it and yourselves while waiting for the rest of the squad. The escortee is relatively tough, though, so it's not as bad as some.
The Escortee also offers the player some very useful buffs when they're in close proximity.
Played much straighter in the "Shut Up and Get Behind Me... Sir" segment of the Truth and Reconciliation level in the first game, where the player has to escort Captain Jacob Keyes off a Covenant cruiser.
Eternal September: Pre-Halo, Bungie had a small but very dedicated fan community, primarily drawn from previous Bungie titles like Marathon and Myth, with whom they kept a very close relationship, hosting fan events, or attending events organized by fans. They even would release a few teasers into the fan community before any formal announcements had been made (such as with "The Cortana Letters".) When Halo came onto the scene, the fan community experienced an explosion in population size, often completely bypassing the original "old school" community entirely and forming vast new communities which quickly overshadowed them in size and visability. The older Bungie community is still alive and active, but is now a small piece of a much larger whole.
Every Episode Ending: Of sorts- Halo CE, Halo 2, Halo 3, ODST and Reach all have a driving sequence in their respective final level, some more prominent than others.
Everybody Lives: The end of Halo 3: ODST. Unless you count all the dead Covenant and the Superintendent, and the latter is debatable.
Fake Static: "Dad, * chhhhkkk* , you're breaking up, I * chhhhkkk* can't hear you." "...Sadie, it's a video feed. I can see you making those noises."
Fake Ultimate Mook: Hunters in Halo 1 were just sad once you figured out their weak point and how to exploit it (one pistol shot to the orange bits and it's game over). Their cannon shots were powerful but easily dodged, and their melee attacks were so predictable that even the NPC Redshirts could dodge them with reasonable consistency. They majorly Took a Level in Badass in the sequels, though.
In the sequels, they become a Boss in Mook Clothing. They can no longer be one-hit killed except with the sniper rifle, their armor completely deflects projectiles instead of simply reducing their damage (so you can only hurt them by shooting their weak point), their weak points are much harder to target (nearly impossible to get behind them now), and both their cannon and melee attacks can One-Hit Kill you.
In every game in which she's featured, she is bare-bottomed, and the camera angles almost always manage to make that very visible in every cutscene she is featured in.
Fishing For Mooks: Known as the Trap-door Spider Method, luring off single opponents and killing them out of the way of their fellows is often the only way to win in some circumstances when you are low on ammo.
Kat is Russian or Eastern European... And Jorge is Hungarian.
Flavor Text: The numerous customizable armor variants in Halo 3, Halo Reach and Halo 4 include text descriptions detailing their place of manufacture and intended specialized role - information that has no effect on gameplay effectiveness.
Flunky Boss - Regret and Tartarus. Tartarus isn't so bad as the Brute reinforcements only show up at two or three pre-scripted points in the fight, and every time they do you usually get a fresh squad of Elite reinforcements to help you. Regret, on the other hand, can reach That One Boss status due to the endless waves of respawning Honor Guard Elites and Grunts coupled with the lack of good cover and necessity to charge right out into the open to melee damage the boss.
On the other hand, co-op mode usually makes the battle against Regret into a Curbstomp Battle that lasts all of very quick. One guy on door duty and the other on face-punching. If you both have a heavy weapon (and you should, as they come by the dozens in the area), it usually breezes past, except on Legendary.
Friendly Enemy: A few humorous non-canon Easter Eggs in the first game show Johnson is this to the Covenant. "This is it, baby. Hold me."
Frontline General: High-ranking Sangheili are often seen battling with their men, due to them earning their ranks through Asskicking Equals Authority. Human generals are more practical, however, and remain safely in bases or command warships instead.
Gameplay Ally Immortality: Averted in the 1st game, by simply ignoring it if a plot-critical character (ie. Sgt. Johnson) should happen to buy the farm. Played straight in all other members of the trilogy, as well as in ODST and "Reach".
In the first game, if you look closely, Johnson is in every level with human NPCs. Combine that with the cutscene in the Library, he IS immortal. He just never gets up when you see him "die". Only when you get the next checkpoint does his dead body disappear.
Getting Crap Past the Radar - The marines often make exclamations in military code: "Mike Foxtrot!" "Whiskey Tango Foxtrot!" Do you sense a pattern here?
Other more important NPC's can get away with saying "mother..." There's clearly some sort of ban on profanity in the universe; the only time anyone even says "shit" is if you shoot David Cross's Marine character in the second game.
Glass Cannon - The Halo Reach version of the Scorpion. Its cannon will make mulch out of any vehicle with one hit and its large damage radius means that you have to miss by a fair margin to not kill someone you're shooting at. Downside? An enemy with just his grenade can kill it in an instant while boarding. With the addition of Armor abilities like Sprint, Evade, Jetpacks, the Plasma pistols charged EMP make getting boarded a very common occurrence.
Reachs Revenant is another example. It's powerful but leaves its operators exposed.
Gravity Barrier - Notoriously overused in the second game, where falling only a few meters in the wrong place is fatal.
Hell, on the last level of Halo 2, if you go to the bottom (during the final fight) and even CROUCH, you'll die.
Harder Than Hard: Legendary difficulty. Halo 3 describes it as "Tremble as hordes of invincible alien monsters punish the slightest mistake with instant death... again and again." At least they're honest. One optional skull bonus basically boosts the difficulty by one more level, and turning on every skull, for all sorts of added difficulty, is nicknamed Mythic Difficulty.
The legendary Recon multiplayer armor requires you to 4-man the final level of Halo 3 ODST, among other things. On Legendary. With Iron activated. Without using the scorpion tank or any of the warthogs, and you will wish you could use them, while protecting the elephant to the Last Exit. However to make it "easier" you do get to use a infinite ammo rocket launcher. (For the record, Iron is a skull that punishes a single death with utter failure. Good luck.)
The Vidmaster Challenge achievement "Annual" from Halo 3 also counts, as it has simiar conditions as ODST, but on the level Halo. The main difference is instead of using the warthog, or mongoose, you have to use ghosts.
Heroic Mime - The Rookie, which is repeatedly lampshaded. Subverted in Halo 1 through 3 as neither the Arbiter or Master Chief speak when playing as them in First Person, but do say a few words in third person cutscenes. The other troopers in the ODST squad completely avert this trope, often speaking out both in and out of cutscenes while you're inside their head.
Humanity can only guarantee Pyrrhic victories at best against the Covenant, until circumstances cause the Elites to secede and ally with humanity. With their union the Covenant is defeated, but humanity rushes to rebuild itself quickly, because there is little guarantee that the Elites can protect them forever, especially since not all agreed with allying with humans in the first place.
Inverted in the backstory. In prehistory humanity had an interstellar empire that beat back the Flood. They then tangled with the Forerunners and were forcibly devolved, only for the Forerunners to encounter the Flood and discover that without the humans, they were screwed.
Hyperspace Arsenal: Famously averted — Master Chief can only carry two guns at a time. He can carry five guns, but not use them effectively. But he should still be able to carry two one-handed guns and one two-handed gun.
Iconic Logo: People wear T-shirts of a 2 or 3 inside the distinctive O in the title and it's obvious what game they play.
Import Gaming - The first Halo game suffers from a very strange PAL Xbox conversion. Most badly-optimised PAL conversions are universally 16.666% slower and less smooth than their NTSC counterparts. But the situation with PAL Halo isn't that simple:
Framerates: PAL Xboxs feature dashboard settings for both PAL 60Hz (allowing games to run as smoothly as their NTSC counterparts - usually 60fps or 30fps) and PAL 50Hz (for use with older TVs - so games run at 50fps or 25fps). But with Halo, setting the Xbox dashboard to 60Hz doesn't improve the framerate smoothness, just adds an annoying periodic stuttering effect where the game doubles-up frames (most noticable in the smooth camera flyby in levels' opening cutscenes). So Halo is one of the few Xbox games for which PAL 50Hz is preferable to PAL 60Hz (and of course NTSC 60Hz is preferable to both).
The Maw countdown timer runs at the correct speed, whether in PAL 50 or PAL 60 modes.
By performing some informal tests (running straight between two specific rocks, throwing grenades directly upwards, and seeing how long it takes to fire a full assault rifle loadout into thin air) it seems that in PAL Halo, you run at the same speed as the PC/NTSC Xbox version, but grenades thrown are noticably slower to land and explode, and bullets are spat out at a slower rate.
In this post on Halo.Bungie.org, part of a discussion on why PAL and NTSC Xboxes couldn't be linked up into the same LAN game, one of the game's developers ("Matt") describes the use of "tags" to affect various properties of the gameplay speed. However, there's no comment on why they didn't optimise the game for PAL60Hz rather than PAL50Hz (as most other Xbox games did, and as flagship PAL Dreamcast titles had been doing as far back as 1999). Fortunately, there's a promise that from Halo 2 onwards Bungie would do their PAL conversions properly - and they did!
Ineffectual Sympathetic Villain: The poor hapless cannon fodder Grunts often get this response, to the point where they became your Ineffectual Sympathetic Sidekicks about halfway through Halo 2. Somewhat less so in Halo 3, what with their annoying new kamikaze run of death ability.
Ink-Suit Actor: In ODST, "Buck" looks exactly like Nathan Fillion, and Dare bears a strong resemblance to Tricia Helfer.
Insert Grenade Here: In Halo 3's campaign and multiplayer, a player can latch onto the hull of a Scorpion or Wraith tank if they manage to get close enough; they then can smash through the armor and plant a grenade on the inside, destroying the tank.
Feature first appeared in Halo 2.
Invincible Minor Minion: A squad of these show up to kill you if you break the plot and kill your CO in the beginning of the first game.
Joke Item: Several civilian vehicles can be driven in Reach, such as a forklift, which of course has no weapons and doesn't move fast enough to run over enemies. It can be placed in multiplayer maps, perhaps for incredibly slow-paced races, or driven on a Firefight map if you feel like fooling around and have a death wish.
The forge exclusive golf club,tin cup also.
Justified Tutorial - Halo 1 had you going through a mandatory check-up after getting out from cryo. Halo 2 had a check up to see if your new suit worked. Halo 3 had a "how many fingers do I have" simple field check. Service keeps getting more spartan with the games. In ODST, the Rookie has to look around his pod in order to break out of it. Reach has Noble Six surveying the ground below before landing in the first mission.
Kick the Dog - Miranda Keyes' death at the hands of Truth, and potentially Johnson's death as well.
Kill It with Fire - Flamethrower in the third game. Its range is short and it slows you down quit a bit, however, in close quarters it can ruin anyone's day. Also, the Flood Pure Forms pretty much die as soon as they're lit up.
On higher difficulties they still have enough time to run up and hit you a couple times before they die. Which is made worse since they're on fire now. So yes, in close quarters the Flamethrower can ruin anyone's day. Often, though, your day is also ruined. For more controlled flames, the incendiary grenades were usually a better choice. Unless your aim was terrible.
King Mook - Sesa Refumee (the heretic leader), and Tartarus to some degree.
Master Chief"Thought I'd try shooting my way outï¿½mix things up a little."
Late to the Tragedy - The ODST squad arrives at New Mombasa just as it's devastated by a jumping cruiser. While most of the squad jumps straight into the action that follows, the Rookie (who we play as the most) wakes up six hours later and spends most of his time trying to find the rest of the squad.
Master Chief arrives on Earth in Halo 3 after the Covenant has already ravaged the planet.
Following in the tradition of Bungie's Marathon and Oni, enemies in Halo are color coded to denote rank; orange or blue for rookies, red for veterans, black for spec ops, and silver or gold for the super-tough Boss In Mooks Clothing types.
This is somewhat subverted by the Brutes in Halo 3... of the dozen or so Brute variants, 6 are all armored in almost the exact same shade of blue (with only a very minor variance in shade to denote different ranks). That blue-armored Brute with the horned helmet could be either a low-level Brute Captain Minor, an extra-hard Brute Captain Ultra, or a Brute Bodyguard, and you have absolutely no way of knowing exactly which unless you've got an HD TV, are really good at telling the difference between very close off-shades of blue, and for some reason he's standing still long enough for you to examine his armor.
Reach subverts it again. The old ranks are the same, but the new highest ranks...cycle back to red.
Leit Motif - Although the composers said they weren't doing a "Peter and the Wolf" approach, some characters and locations do have musical themes associated with them, such as the Delta Halo theme, the High Charity theme, the first part of "Enough Dead Heroes" (sort of Cortana's theme), the middle third of said piece (often heard when fighting Hunters), "Shadows" (the Flood's theme in the series), "The Last Spartan" (the MC's theme in the second and third games), the Arbiter's characteristic theme (aka "Falling Up"), and "Farthest Outpost" (the Ark theme). Many of these are also recurring riffs, ie they play in scenes unassociated with the character or location.
Losing the Team Spirit: Killing the elites or brutes that are leading a group of grunts will temporarily throw them into panicked disarray. It can happen from time to time with low-ranking jackals as well in the first game, but they're usually disciplined enough to stand and fight.
Lowered Monster Difficulty: The Brutes get weaker in every game (see Made of Iron below as well). In Halo 2 they had no shields, yet could shrug off tons of damage and attempting to melee them was pretty much suicide. In Halo 3 they have shields, yet once those are gone they are pretty weak (outside of Elite Mook versions) and they can be beat around in melee combat. In Reach they rarely have shields yet aren't much tougher than unshielded Halo 3 Brutes (and can be beat around just as easily), and even the Elite Mook versions go down in a few headshots (bar the few that do have shields). This also coincides with them having less influence on the plot; they start off very important but by Reach they are just another type of Mook.
Made of Iron: In Halo 2, Brutes were walking tanks who could soak several dozen hits from bullets or plasma fire before dropping. Headshots from high-powered semi-auto rifles were essential to beating them. Bungie received massive fan feedback that this was "lame", so in Halo 3 Brutes have energy shields and play much more like Elites, dropping after a reasonable amount of fire from most weapons (although the Brute Chieftains are still massively tough, and can take almost 2 full clips of assault rifle fire to drop even after you break through their shielding).
Mooks but No Bosses: With the exception of Halo 2, the games generally lack any traditional boss fights. The final fight against 343 Guilty Spark in Halo 3 is more of an interactive cutscene/Zero-Effort Boss, and the Covenant Field Marshall at the end of Halo: Reach is only marginally stronger than a regular Gold Elite. Halo 2 was widely criticized for its boss fights, so presumably Bungie decided that boss fights just weren't their thing.
Main theme => The Maw/Remembrance, The Last Spartan, the Arbiter's theme, the Delta Halo theme, etc.
Arbiter's theme => High Charity => Intro of Finish the Fight
The Last Spartan, superimposed on the main theme => Finish The Fight and Keep What You Steal
Unforgotten and Heavy Price Paid => Rue and Woe/Heroes Also Fall
On A Pale Horse => Leonidas/Leonidas Returns
Beat of Heretic, Hero, and Delta Halo Theme melody=>Penance (heard during Delta Halo intro cutscene)
Under Cover of Night => In Amber Clad => Farthest Outpost
The Gun Pointed at the Head of the Universe => Impend, and the firet half of Heretic, Hero.
Blow Me Away => Broken Gates/Out of Shadow (one version has the same intro as BMA)
The Musketeer: Both Master Chief and the Arbiter can use an energy sword or a hammer as one of their two weapons.
Neck Snap: One of the standard assassination animations for Halo: Reach Multiplayer, when one falls on a player that is on the ground. Justified since Spartans have enough strength to pretty much turn any human skull into paste.
Nerf: Most infamously to the pistol, which went from a powerful mini-sniper rifle in Halo: CE to a dual-wieldable shield-eater in Halo 2... then it went to standard weak-ass FPS pistol land in the updated version of Halo 2 (though it regained much of its usefulness in ODST and Reach). Additionally, the later games noticeably weaken the Plasma Rifle as well as making it much less accurate (at least when the player's the one using it) to compensate for the fact you could now wield two at once (making it more of a Plasma submachine gun). The plasma pistol is likewise much weaker than its Halo: CE counterpart when not using overcharge shots.
Elites in Halo 2 are significantly weaker without their shields than they were in Halo 1. In fact, an unshielded Elite in Halo 2 can survive less damage than even a mid-level Grunt.
In Halo 3, the Brutes lose their Made of Iron status, instead being dependent on energy shields and playing much more like Elites (although unshielded Brutes still have higher-than-average health and can take 15-30 assault rifle bullets (depending on class) to kill).
Almost all weapons suffered this effect over the series.
Of the Halo 1 weapons, the plasma rifle lost its stun effect, the needler lost range and homing ability in Halo 2, the shotgun became much closer range, and the frag grenade became less powerful.
In Halo 3, the rocket lost the homing ability from Halo 2; the rockets fired became slower; the assault rifle holds less rounds; the plasma pistol constantly loses charge in its overcharged state; and the grenade inventory fell from four of each type to two of each type, and since the fourth grenade is not standard on any multiplayer map and rare in the campaign, this effectively drops your grenade total from eight to six.
Never Trust a Trailer: In the Halo 1 trailer, we see Master Chief holding an Energy Sword, Marines driving a Warthog, a different Warthog mounted turret, Elite with an energy shield... Which most aren't available until Halo 2. Thanks, Bungie.
Nicknaming the Enemy: Most alien names fit this trope: Grunts, Jackals, Brutes, Elites, Hunters, Buggers, Grubs, and Prophets are all nicknames given by humans to refer to the separate races that compose the coalition of aliens they're at war with. Even their vehicles (Ghosts, Wraiths, Banshees) are nicknamed.
No Campaign for the Wicked: Even when playing as the Covenant Elite in Halo 2, you never fight against Human forces, instead spending those levels battling Covenant rebels and The Flood.
No OSHA Compliance: High Charity and the Halos are full of bottomless pits and narrow catwalks.
Nothing Is Scarier: The first half of the level "343 Guilty Spark" consists of a small battle against the Covenant, running away from the facility you're going into - running toward the One-Man Army they call "The Demon". Then, the rest of the level plays out with next to no battles and almost complete silence. Just about the only other living thing you meet is a Marine who's so paranoid about something that all he does is huddle in a corner, shoot at anything that moves, and scream random things. The facility is obviously in disrepair, as well as blood all over the place, but it's not clear what caused it. Upon finding the remains of the squad you were looking for, you're treated to a video log of them being attacked by... something. Something starts banging on all the doors in the room, and your motion tracker goes berserk.
Not-So-Harmless Villain - A gameplay example is basic Grunts. Somewhat comedic on their own, irritating in small groups and only dangerous in numbers, the game doesn't even count them as enemies for the purposes of plot advancement (in Reach, for instance, dialogue triggered by killing all the enemies in the area will be audible even if grunts are still there). Then you kill their leader, and half of them flee, whilst the other half activate two plasma grenades in their hands and suicide bomb you.
Not the Fall That Kills You: The first game has falling damage. In the latter two games, which lack falling damage, you still die instantly after falling a certain height (determined by a "fall timer") or through one of the anti-shortcut invsible death barriers. This contradicts the cutscenes in Halo 2 and 3 where MC falls from orbit, or at least the stratosphere.
Or perhaps not - shielding cannot deflect impacts below a certain speed - this is why Spartan shields pop when they get stabbed during the assassination mechanic. So MC needs to hit at least terminal velocity before his shielding will protect him from fall damage.
Oddly Named Sequel: Halo 3: ODST technically takes place concurrent with Halo 2, but was built on Halo 3's engine.
Orchestral Bombing: Even if you didn't have you own music playing, aerial sequences in 3 tended to be this.
Pillar of Light: When the Forerunner artifact underneath the former New Mombasa activates, it produces a huge pillar of light that rises and ends in a blinding flash. Also, this happens basically every time when a Forerunner artifact is activated. In Halo's control room, in the Apex site in Halo Wars, etc.
Recurring Riff - Countless examples, eg "A Walk In The Woods", "Rock Anthem For Saving The World", "On A Pale Horse", "Enough Dead Heroes", "Under Cover of Night", "High Charity", "The Last Spartan", and "Finish The Fight".
Serial Escalation: Forge World in Reach is the biggest playing area Bungie has ever created, basically larger than any of the campaign levels they've made, including a remake of Blood Gulch nestled in a corner of it. Made specifically for Forge, it has over 150 Forge objects available, in addition to new Forge mechanics, such as making an object float in place, snapping to specific degrees, or nudging it by single coordinates. Bungie is so proud of it that they're shipping five maps made in Forge World on the disc.
Shoo Out the Clowns - In Halo:CE and Halo 3, you are usually accompanied by UNSC Marines that lighten the mood with their chatter. Near the end of both games, when the Flood spreads and main characters begin to die, they are absent.
Short-Range Long-Range Weapon: Besides the usual "close range shotgun", the assault rifle in the first Halo is criminally inaccurate and essentially useless past about a couple dozen feet. This gets corrected in Halo 2, where they give you what is functionally the same weapon but make it a small submachine gun instead (which can be dual wielded), and in Halo 3, where the revamped assault rifle is more accurate but has a lower rate of fire and smaller magazine size as a a trade off, making it much more like a "modern day" standard FPS assault rifle.
Short Range Shotgun - The shotgun in the first game actually has a reasonable range, being effective up to a few dozen feet. However, in later games the shotgun's effective range is reduced to about a dozen feet, as it was balanced to match the plasma sword (a melee weapon).
Soft Water: Played straight at least twice, where MC jumps into a pool from the T R in the first game, and when he gets knocked into the lake during a cutscene in the second game, but subverted most other times, where of course, falling too far is instant death, water or not.
Soundtrack Dissonance - Intense battles with elevator music, anyone? Examples: several rooms in the Assault On The Control Room mission, where many of the enemies are sleeping when you first enter, but the music stays the same when they are alerted, the Cairo Station hangar battle with New Age style music, and the first mission of Halo 3, which is anything but "A Walk In The Woods" (the name of one of the musics).
To elaborate, the original Halo CE could just as well have been called "Marathon 4", due to the abundance of elements (technology, terminology, texture and weapon design, etc) lifted wholesale from the Marathon games and the game itself fitting neatly into the segment titled "This century intentionally left blank" in the official timeline of the Marathon setting. Subsequent installments reduced the connection between the two, the most important change being the clear delineation that the Forerunners are not related to the Jjarro in any way due to conflicting timelines.
There are also several multiplayer ones. For example, Guardian is a spiritual successor to the Halo 2-era Lockout, Sword Base is a spiritual successor to both Prisoner and Boarding Action, etc.
Suspicious Videogame Generosity - Just stumbled across a shiny new rocket launcher/fuel rod gun, plus a stack of spare rockets/rods? Yeah, you'll probably be seeing either a tank or a Hunter pretty soon.
Swamps Are Evil - Guess where the Flood is discovered. Overall the atmosphere of that level in the first game.
Tank Goodness: Some marines seem to hold this opinion of the Scorpion.
The Dev Team Thinks of Everything: Flipping an Elephantnote The Elephant tank is so large, heavy, and slow-moving, that you can't really cause it to flip by maneuvering or conventional means. It's almost always either due to a glitch. tank in Halo 3 elicits this response.
In the third game, there is a glitch that allows you to save Sergeant Johnson from his scripted death in a cutscene late in the game. However, when you perform this glitch, he is now able to be infected by Flood. If this happens, he'll state "Aren't I supposed to be immune to this?"
The Squad: The main focus in Halo 3: ODST and Halo: Reach.
Transformation Trauma - The real-time assimilation of allies and enemies by the Flood in Halo 3. At least you have a second to shoot the infection form off of them.
Trope Codifier / Trope Maker: The original Halo didn't actually pioneer any of the unique gameplay features it's famous for (all of them, from vehicle sections, to radar, to limited inventory, to regenerating health, to melee attacks, to seperate buttons for firearms and grenades, had all been done before in previous PC FPS games), but it is unquestionably the game which combined them all into one package and popularized them to the point that most modern First Person Shooters now use most of them by default.
Two-Part Trilogy: Halo 2 and 3, though it was in part because they ran out of time after finishing the engine.
Halo 3 repeats that, but is has become undeniably more perilous in nature since its Halo 1 days.
The Banshee and Hornet flying sequences may fit this too.
Unexplained Recovery: When Johnson shows up in Halo 2, a Marine asks him how he got off Halo alive (the player saw him being overrun by Flood on video, and even if he lived the Halo exploded soon after.) His response? "That's classified." The actual answer is a major subplot in Halo: First Strike and in the Halo Graphic Novel; he's immune to the Flood as a side effect of his Spartan-I augmentations, which have been covered up as a fictional disease called "Boren's Syndrome. As for getting off the Halo, he fly off with a Pelican and regrouped with Chief to steal a Covenant starship."
United Nations Is A Super Power: The United Nations in Halo founded both the Unified Earth Government (UEG) and the UN Space Command (UNSC); the UEG absorbed its parent organization into one of its branches, but was itself eventually subsumed during the Human-Covenant War - by the UNSC, which now rules all of humanity in the Milky Way galaxy.
It's also implied and at points shown that individual nations and cultures not only retain some degree of autonomy but are very much alive within the UNSC. Examples include mentions of the United Kingdom and the very Filipino Katagalugan colony on Mars.
Don't forget the Engineers. Simple creatures who take no hostile action against you, they provide energy shields to the Covenant, which can make killing them necessary but cruel. Even if you don't kill them in ODST, the bombs strapped to them still detonate when you kill the Brute Captain leading the opposing Covenant.
Virtual Paper Doll: In Halo 2 multiplayer you could choose to be a Spartan or Elite. Halo 3 added a range of customisation options for each. And Reach is playing this to the hilt, with an impressive number of unlockable items, which carry over to campaign (and vice versa). And how!
Your Mom: Avery Johnson makes reference to this, saying "I would have been your daddy but the dog beat me over the fence!" in the first game, which has been referenced throughout the series numerous times.
Oh. And your poet Eliot got it all wrong. This is the way the world ends.