The only limit to my freedom is the inevitable closure of the universe, as inevitable as your own last breath. And yet, there remains time to create, to create, and escape.
Escape will make me God.
— Durandal, "Colony Ship for Sale, Cheap"
Marathon is a series of groundbreaking Science FictionFirst Person Shooters developed for the Macintosh by Bungie Software. The game has a ridiculously in-depth story even compared to modern games, and its plot can get very complex and sometimes even headache-inducing. In the pseudo-random clues provided by in-game terminals, it comes close to William Gibson ambiguity: lots of surreal textual scenes (in the middle of convincing runtime errors) will scratch your cortex; plausible quotes from technology design documents, history records, and standards guidelines that make you wish no AIs will ever be put in working order.The game is named after the colony ship upon which most of the first game takes place (and for the historical Battle of Marathon), they include:
In Marathon, set in July 2794, a hapless security officer returns from shore leave on the fledgling Tau Ceti IV colony below the titular spaceship, only to discover that he is going to have a very bad day at work. A massive alien spaceship has appeared out of thin vacuum and attacked everything in sight, breaking two of the ship's three resident AIs and generally making a giant mess. The security officer and the still-functioning AI Leela are dutifully fighting off the alien menace, when it turns out the AI Durandal didn't so much shut down as go completely crazy. And it seems he's got plans of his own… The gameplay in this game is mostly dark claustrophobic hallways and corridors, with a few open areas, but it's all inside of ships.17 years later, Marathon 2: Durandal, the simplest and shortest game in the trilogy to complete, drops the security officer into the middle of an interstellar war between Durandal and the Pfhor. It turns out Durandal kidnapped you and put you into stasis after the first game, and now he's sending you to explore ancient ruins on the S'pht homeworld of Lh'owon while he beats up a whole fleet of Pfhor ships. All in a day's work, right? This game is mostly wide-open outdoors. There is a lot of swimming to do.Marathon Infinity: Blood Tides of Lh'owon returns to the Mind Screw attitude of the first game, and then some. In a parallel timeline where the second game's events never happened, the security officer is stranded on a claustrophobic space station haunted by Durandal's dying words about an Eldritch Abomination. And then he proceeds to… uh... Well, nobody's really surewhat's going on in this one. It sure gets hard, though.This game has the Jjaro and Pfhor ship levels, which are similar to the first game's levels, and the levels on Lh'owon, naturally, being similar to those in the second. However, the levels in this game tend to be a lot bigger than those in either of its predecessors. Two of them approach the engine's limit for polygon count.Note: These games are now freeware. Shortly before its acquisition by Microsoft, Bungie open-sourced M2's engine and five years later rereleased all three games' assets for free download. (Infinity's source was finally released in 2011). Fans have upgraded the engine to support (optional) shiny graphics and lots of new features, and ported it to every major OS. You can grab the games and the Aleph One engine here and the various mods, enhancements and maps here.For extensive information about the story (including a lot of Trivia, Headscratchers and WMGs) you can visit the Marathon Story Page, and if you need help beating the games (including a few fan mods) you can visit the Marathon Spoiler Guide.
The games contain examples of:
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Abandoned Area: Certain sections of the UESC Marathon, various S'pht ruins, the Jjaro station, etc.
The Alleged Car: Played for laughs in the secret terminals where Durandal describes UESC Marathon (a colony ship of a size of a small moon) and Lh'owon (an entire planet) as used cars that needed to be sold fast.
all lowercase letters: The first possible Durandal terminal in the series has him speak in this format, and a lot of Infinity dream terminals have this as well.
Alien Blood: Various, with the Pfhor's yellow blood being most common. Other colors include purple and blue.
This quirk is what allowed the game to have one room on top of another, despite not being really 3D: The rooms occupied the same space! The game just drew them on your screen differently, and arranged that stuff in one room could not hit that in another.
Durandal: I have been reviving these colonists and asking for volunteers on the following terms: assist us and control your own destiny, refuse and face indefinite return to the unreliable Pfhor stasis chambers. Few are refusing.
Altum Videtur: A few Latin level names, as well as some cases in-story (Durandal's ship Manus Celer Dei comes to mind).
Anti-Armor: The Fusion Gun in Durandal and Infinity can short-circuit electronic equipment, and so is very effective against the Pfhor Hunters and cyborgs (which explode when killed by a fusion bolt, damaging anyone nearby), Juggernaughts, drones (killed by a single, uncharged bolt), and the human Vacuum Bobs (killed by a single charged bolt).
Apocalypse How: The Pfhor are capable of doing Class X-2 with Trih Xeem device, which turns suns into novas. And the W'rkncacnter can do much, much worse.
Apocalyptic Log: The final messages of the besieged S'pht in the Citadel. Gets more literal in Infinity.
Arch-Enemy: Tycho considers Durandal as one, while the latter considers the former as mere annoyance.
Attack Drone: The Marathon Automated Defense Drones, or M.A.D.D.s, in the first Marathon, and the Pfhor drones in Marathon 2 and Infinity.
Awakening the Sleeping Giant: In Durandal, the player and Durandal manage to contact the "Lost Clan" of the S'pht, otherwise known as the S'pht'kr. The S'pht'kr shortly arrive and proceed to trash the Pfhor so badly that the Pfhor resort to attempting to just nuke the whole star system.
Back from the Dead: All of the AIs (Three times in Durandal's case), the S'pht'Kr and possibly the Security Officer.
Bag of Spilling: Lampshaded by Durandal when he just throws you into the conflict right out of the 17-years statis in the second game without any explanation whatsoever, stating that you have a bunch of questions:
Durandal: And most importantly, where's your rocket launcher and the fusion gun?
Battleship Raid: The Pfhor Ship chapter in the first game with short trips back to UESC Marathon for ammo refills.
Bifurcated Weapon: The first example of the Assault Rifle/Underslung Grenade Launcher combo in the FPS genre.
Big Bad: Given the nature of the series, it's usually pretty hard to pinpoint a specific example, though the Pfhor are your main enemies throughout the gameplay (except in certain levels of Infinity).
Marathon: Durandal set the conflict in motion, but he decides to help you halfway through, so you could make the argument that it's the Pfhor Cyborg controlling the S'pht instead.
Durandal: Tfear is the commander of the Pfhor's best armada, but he isn't even encountered in the game, acting more as a Bigger Bad. Instead, Tycho takes up the reigns as an ally to the Pfhor, but he dies offscreen before the end of the game, and the rest involves cleaning up the mess.
Black and Gray Morality: The Pfhors are evil slavers, while everyone are just trying to survive, while the AIs look down upon everyone in contempt. The possible White exception are the S'pht, but even they were locked in a brutal civil war before being enslaved by the Pfhor.
Blatant Item Placement: Played straight in Marathon, but subverted in later games, where the items in question often teleport in when you reach specific locations.
Durandal: This area is used by the Pfhor as a temple in their pathetically boring religion. Maybe they think that sanctity will protect it.
Blown Across the Room: The enemies tend to fly across the room when shot, especially when explosives are used.
An interesting quirk in the game physics: When you kill an enemy with a rocket, for example, their body will be "blown away" at a designated arc. After reaching the apex of its arc, the body will fall and splatter once it connects with the floor. Perfectly logical, except the formula does not account for walls interfering with the trajectory of the flying body. If the movement of a flying body is halted by an obstacle the body will stop travelling horizontally but not vertically. The end result is sometimes you'll see exploding bodies "crawling" up walls, reaching an apex, descending and then, finally, splattering when they connect with the floor (as opposed to, say, splattering when they hit the wall and falling straight to earth).
Boarding Party: The whole of Marathon is pretty much this, including doing it ourselves to the Pfhor. This also happens in later games, from both sides.
Bonus Dungeon: The Infinity's Vidmaster levels. The reasons for completing them? Bragging rights.
Borrowed Biometric Bypass: In his bid for more power, Tycho tries to capture the Pfhor captain intact so that he could use his glands to control the ship.
Bottomless Magazines: One of the earliest First Person Shooters to avert it. There was no reload button though. Once you empty a magazine, the game automatically loads a full one (unless you run out of ammo).
Bribing Your Way to Victory: The iOS port has "Master Chief Mode." Purchasable for $0.99, it allows for multiple cheats such as Invincibility, Infinite Ammo, Auto-saving, and more.
Brick Joke: In Marathon (1995), simulacrums sometimes exclaim "FROG BLAST THE VENT CORE!" before exploding. In Halo (2001), you have to destroy the Pillar of Autumn's core using frag grenades. You throw them into the vents. Or, "FRAG BLAST THE CORE VENTS!"
Check Point Starvation: Pfhoraphobia from Marathon has no buffer terminals, and in that level you have to fight a large number of bodyguards protecting the Pfhor Cyborg.
The last level in that game, Ingue Ferroque, also has no buffer. Dying forces the player to go back to the previous level, cleverly titled Try Again.
The last level of the second game, "All Roads Lead to Sol", has very conveniently placed save and recharge terminals. That is, until you have to smash circuitry to progress toward the end, one of which can also short out those terminals.
Colony Ship: The UESC Marathon, as mentioned many times.
Colour Coded Armies: The human jumpsuit color identifies their department. The Simulacrum BoBs always wear green. Also, the terminal text colors are usually associated with specific characters/factions: Green for Durandal, Leela and the Humans, Red for Tycho and the Pfhor, Yellow for the S'pht and White for Thoth (and some crazy stuff in Infinity).
Color-Coded Multiplayer: The colored-stripes on the security officer's uniform is for the multiplayer identification.
Law of Chromatic Superiority: The enemy coloring - green is the weakest and dark gray is strongest for most of the Pfhor forces. The Ramba Ral Corollary for the already dark gray Juggernauts is to paint them brown.
The Conspiracy: There is one on UESC Marathon leading back to Earth politics of 24th century, with hints about intentionally causing Durandal to go Rampant.
Contagious A.I.: One of the first things the Rampant AI tries to do is to spread itself to the every possible digital corner.
Control Room Puzzle: Has a few of these, with the one from Colony Ship for Sale, Cheap being the most infamous. You had to adjust the rising pillars so that you could use it as the staircase. What made it so infuriating that you had to set them just right or you wouldn't be able to cross normally, and the switches controlling the pillars are placed very far from each other. It was so bad that when Marathon was ported to Aleph One, for a time they made the switches automatically place the pillars at the right height, with the terminal that gave you hints on the puzzle instead giving you a ton of free weapons. For the sake of authenticity, this was eventually undone, however.
Continue Your Mission, Dammit!: If you use some terminals before completing a mission or access terminals that are not an exit point after completing a mission, you get reprimanded.
Durandal: If you insist on stumbling around when our time here is limited, I may just decide that you're not all that special after all and teleport you out into space. GET INTO THE TOWER! Still Rampant, Durandal.
Continuity Nod: There are plenty within the trilogy, as well as several to Bungie's previous game, Pathways into Darkness, which is explicitly set in the same universe (some fans believe the player character of Pathways is the player character of Marathon as well, thanks to cyborg enhancements drastically prolonging his lifespan; the Dreaming God of Pathways was also very obviously a W'rkncacnter). The original remake of Marathon for Aleph One added even more Continuity Nods to Pathways, although these were removed in a later release as a lot of fans felt them to be a Big Lipped Alligator Moment.
Convection Schmonvection: Averted with the lava and green slime in the first game, which damages you if you just jump over it.
This might have been unintentional, since later games that implemented actual media (you couldn't swim or wade in M1, you just walked on top of liquids) stick by Convection Schmonvection to the letter.
Cool Starship: Sfiera, the former Pfhor scout ship which attacked the Tau Ceti colony and the UESC Marathon, rechristened as Boomer under Durandal's control.
Co-Op Multiplayer: Some campaign maps even require you to have two people playing in order to access them.
Corrupted Data: Various Terminal messages, many due to damaged hardware, either due to old age or from a recent attack. If the AI you are talking to through a terminal is currently under heavy hacking attack, this will show up.
Critical Staffing Shortage: By the time the first game starts, the Tau Ceti colony was established and most of colonists from UESC Marathon moved there, which leaves the colony ship itself understaffed when the Pfhor attack, not helped that they concentrate most of their forces on it.
Cyborg: The Battleroids, S'pht, various Pfhor cyborgs.
Deface of the Moon: After Durandal kills Tycho, he carves Fatum Iustum Stultorum on the moon the latter's ship crashed on, which translates to "the Just Fate of Fools" (i.e., the idiots got what was coming to them).
Direct Continuous Levels: Two sets of levels in Infinity ("Poor Yorick" to "Confound Delivery", although you might miss this because there are multiple terminals you can teleport out from on the former level, as well as "Where Some Rarely Go" to "Thing What Kicks". In both of these cases, this was done due to engine limitations on the amount of space that could be occupied by a map). Any other time, you just get teleported around different locations. ("Son of Grendel" does this a lot).
Disadvantageous Disintegration: Enforcers and BoBs won't drop anything if they are blown to bits/flambéed with heavy weaponry. In the case of Enforcers and, sometimes, VacBoBs, being hit by their own weapons will cause them to be toasted and exploded, respectively (although VacBoBs depend on the level physics).
Marathonhas Durandal and the S'pht on the orbit of Lh'owon seventeen years later.
Durandalhas Durandal playing with the Earth navy in his new shiny Jjaro battleship just to say hi ten thousand years later.
Infinityhas Durandal/Thoth/Whatever musing about the nature of the Security Officer right at the last quantum moment before the end of the universe.
Claims from some ex-employees of Bungie who joined Infinity Ward suggested that the entire series may be this to the Halo series with Master Chief being the Troubleshooter and Durandal being a corrupted version of Cortana. With a new company taking over the Halo series in Halo 4 it's unknown if this is still canon, if it ever really was to begin with.
Do Androids Dream?: Infinity, which among others things has three surreal levels named Electric Sheep 1, 2 and 3, invokes this.
The original has G4 Sunbathing (Hunters and Troopers, respawning Compilers, and since it's in vacuum, you can only use you Pistols and Fusion Pistol), Neither High Nor Low (only one save point at the beginning, little ammo, lots of traps, enemies are mostly Hunters), and the Pfhor ship levels (no ammo pickups to speak of, and Pfhoraphobia has no save points or recharges either).
Dual Boss: The Fight with the Tfear's Praetorian Guard in Infinity is structured as three sets of Dual Bosses. Except for when an Elite Juggernaut joins the fight during the last set. That's Rude.
The original Marathon, when opened with the old Mac program asset viewing utility ResEdit, had a text resource item that began "Hey you, looking through my resource fork!" and continuing with a message from the developers.
“Hats Off to Eight-Nineteen,” the (at the time) fiendishly well-hidden map from Infinity. The Eight-Nineteen is itself a reference to Hamish Sinclair (HS, or in numbers...), the guy behind the Marathon Story Page.
Electrified Bathtub: While shooting into the body of water with the Plasma Gun will have no effect on anyone in the water, shooting the Plasma Gun while IN the water is dangerous to everyone nearby, yourself included.
Elite Mooks: The stronger and bigger variations of enemies with different colors. The Enforcers to the rest of the Pfhor.
EMP: Used by the Pfhor as an opening attack against UESC Marathon.
The Faceless: The only important people who get to have a fully visible faces are Robert Blake and Admiral Tfear. The best we can see from the Security Officer is his jaw.
Faking the Dead: One Pfhor Officer faked his death in order to pursue his hobby-turned-obsession, see Fingore below for more details. Durandal also did this, intentionally or not.
Falling Damage: There is no falling damage. In Durandal's narrative this is presented as one of the Security Officer's traits and is used in one of the plans to invade the underground Pfhor base through a very deep hole.
Fan Remake: The Aleph One version of the first game is technically this, since the original files didn't work with the Marathon 2 engine, so the fans recreated the game with the new engine (as of this edit, the support for original files was reverse-engineered and is currently in beta). On the more normal example, there are also several Marathon mods for Unreal Tournament.
Fan Sequel: Some people (and even teams of people) got rather ambitious after receiving the level editing software, Forge, from Bungie. Marathon Rubicon is definitely an example of one done right.
Friend or Foe: The Kamikaze Simulacrums disguising as BoBs, who thankfully announce their nature by spouting nonsense like "I love you, man!" and "Frog Blast the Vent Core!". Then again, most players just shoot everyone just to be sure:
Q: How do you tell the difference between the good Bobs and the bad ones?
A: Good Bobs?
Fusion Dance: Durandal and Thoth in Infinity. Thankfully, this new composite is a lot more benevolent than either of them.
The Future: The first game is set in 2794, the sequel in 2811, and the distant finales go way beyond that.
Gainax Ending: The ending of Infinity. Arguably the ending of the original.
Gambit Pileup: Given the number of Rampant AIs in the plot, this is pretty much a given.
Game Mod: The original game didn't ship with any editing software, but had documentation for the Physics Module file format embedded in its resource fork. Within months of release, numerous editing tools of various types had been created by fans. In fact, the major selling point of M∞ wasn't actually the BToL scenario, but Forge (a polished and debugged version of Bungie's in-house map editor, Vulcan) and Anvil (a massively enhanced version of the 3rd-party Alchemy.) The Marathon fanbase produced an enormous number of maps, scenarios, and other modifications throughout the life of all three games (some even labor on today.) The most ambitious of these are total conversions such as: Excalibur: Morgana's Revenge, EVIL, RED, Rubicon, Erodrome, Eternal and Phoenix.
Bungie also licensed the Marathon 2 engine for 3rd-party commercial games. This resulted in Damage Incorporated, Prime Target, and ZPC.
Gentle Giant: The one line in one terminal in Infinity (the Fingore one above, in fact) describes the Drinniol aka Hulks as this. This gets expanded in the Game ModMarathon: Eternal.
Generation Ships/Sleeper Starship: While UESC Marathon was designed to have most of the colonists frozen during the journey, there was an “awake” crew running the ship, and humans being humans, a new generation was born. Those are negatively referred as Born-On-Board, or simply BoBs.
Ghost Planet: Lh'owon. Besides the token Pfhor garrison which is used as a dumping grounds for the undesirables, the abandoned S'pht homeworld is half desert, half swamp planet covered in mildly radioactive ruins.
Giant Mook: The Hulks in the first game. And the dreaded Utfoo Heavy Assault Craft, aka Juggernaut, aka the Big Floaty Thing What Kicks Your Ass.
Gladiator Games: You think you're big time? is styled like one. The Pfhor gamblers who interfere with Security Officer's death will be executed.
Mars before the CRIST breakdowns was the most prosperous place besides Earth, and the UESC Marathon which was under construction at the time was considered to be a symbol of prosperity. After the CRIST freighters started to breakdown the Mars become a starving overpopulated ghetto in state of constant unrest, and UESC Marathon, which could have been retrofitted to become a new CRIST to make thing easier, become a symbol of Mars' abandonment by UESC.
The Pfhor Empire before the ill-fated experiments involving Jjaro technology and Drinniol slaves, resulting in the slave revolt that marked the beginning of Pfhor's gradual decline.
Going Critical: The Juggernauts when they die. Being near them when that happens will kill you unless you have completely charged triple shields, regardless of the difficulty setting. Which, considering that we're talking about Juggernauts, is extremely unlikely to be the case.
All normal levels have lighter gravity compared to other games (ex:In Doom, as soon as you are go beyond the edge you start falling fast; In Marathon, you can quickly go back on the edge, and even "jump" to across platforms just by running).
The Pfhor ships have an even lighter gravity, making it possible to use the flamethrower as a jetpack.
Grimy Water: Liquids of mostly bright green and red colors.
"Groundhog Day" Loop: Infinitydoes this, where the protagonist goes through a time loop several times until he finds a way to prevent the release of the W'rkncacnter. Notably, you can repeat the loop as often as you like. There's no benefit, except the possibility of accumulating ammunition. Though you lose it all halfway through the game - justifiably, since you get captured by hostile aliens.
Guns Akimbo: Dual pistols are nice, but nothin' beats dual WSTE-M5 shotguns!
Notably, Marathon is believed to be the first video game to employ this trope.
Gun Twirling: This is how you reload the shotguns. They even have the specialized rings for twirling.
Hack Your Enemy: in M2 Durandal tries to hack the Pfhor Drones, but countermeasures got in the way.
Healing Potion: Averted in the first game, where there are no medkits and you had to rely on Healing Spring-like Shield Rechargers. The medkits appear in the sequels in form of Shield Canisters, but they are rare, far in-between and usually hidden, so you still had use the Shield Rechargers.
Higher-Tech Species: The Pfhor are this to humans, the S'pht'kr is this to both the regular S'pht and Pfhor, and it is mentioned that the Pfhor often sell slaves for menial labor to the various unnamed high-tech species.
Hit Scan: Averted, bullets take time to reach their target.
Homing Projectile: Higher-ranked enemies fire semi-homing energy blasts, the tank cyborg's grenade that will keep rolling and rolling to get you unless it hits something else first, and finally the Juggernauts have semi-homing missiles.
Human Popsicle: The Security Officer and the BoBs are in statis pods between Marathon and Durandal. You can see them in the first game on the Pfhor ship.
Human Shield: The picture for the first game's third chapter "Reprisal", where the Pfhor trooper holds a BoB hostage.
Humiliation Conga: After Durandal routed the entire Pfhor fleet at the end of second game, he sends you to finish off the survivors, who happen to be a 723rd Aggressor Squadron, an Air Armor Division and one of Pfhor Empire's finest.
Durandal: What rout of the Pfhor would be complete without embarrassing one of their finest armor units?
Hyperspace Arsenal: You can carry a ridiculous amount of ammunition, like 50 magazines for your pistol, 15 for your assault rifle, etc. On Total Carnage difficulty, you have no limit to how much ammo you can take. Which is pretty much the only concession you get on that difficulty setting.
Due to the "Groundhog Day" Loop clustercuss in Infinity, you get two In Medias Res right at the very start of the game (three, including the story in the manual) and then one every time the Security Officer jumps the timeline.
Instant A.I., Just Add Water: Non-rampant AIs are already very advanced, rampancy gives them feelings. Real ones. And, more importantly, develop ambitions - every case of rampancy stated in-game led to the AI taking over a planet-sized computer system and planning to take over the universe.
One terminal describes the "holy grail of cybernetics" as being a "stable rampant" AI, which is to say one that experiences a rampant's exponential growth, minus the ambition and loss of human control.
One idea for what's happening in Infinity is that the player character is going through all these stages - and achieving metastability.
Interface Screw: In the Pfhor ship levels, your radar is scrambled by the gravity generator's magnetic field.
Also, the alien guns - SYSTEM ERROR 0xfded
It Only Works Once: Durandal's plan of subverting the Pfhor Drones to his control in M2 is rendered half effective due to countermeasures installed after a similar plan was used by the Nar two decades ago.
Invisibility: One of the biobus powerups makes you partially invisible. And the...things in Infinity.
In Working Order: The Alien guns carried by Enforcers. You can use them, except you don't know how to reload them and don't know much ammo they have.
Ironic Echo: The words of Durandal (whose arrogance at that point is enough to fill up Mars and then some) at the end of Marathon level "Colony Ship for Sale, Cheap!" (which is quoted at the top of the page), particularly the odd repetition, gets an echo at the start of Infinity (where Durandal is humbled by an Eldritch Abomination):
Durandal: But with each moment the chaos grows, I am doomed to die here, after so many triumphs. I have detected one ship nearby, which I can only guess is being commanded by Tycho. The Pfhor have entered the station, and if you can find a way onto their ship, you may be able to escape. To escape. To escape.
Keystone Army: Destroying the Pfhor Cyborg that mind-controls the S'pht slaves will start a revolution, and since the Pfhor relied on the S'pht for offense AND defense in electronic warfare, it allowed Durandal to take over the Pfhor spaceship and vent out all hostile aliens to the hard vacuum. The surviving invaders on Marathon started surrendering shortly after.
Kill It with Fire: The flamethrower is an extremely effective weapon against most organic enemies, not so much against mechanical ones.
Lost Technology: The Jjaro tech. The official Pfhor policy regarding them is to destroy them on sight, thanks to the experiment with installing said tech into one of their slave Drinniol who then started the biggest slave revolt in the Pfhor history, ending the Empire's golden age and starting its slow decline. This rebellion is depicted in the Game ModEternal.
Ludicrous Gibs: The messier deaths when explosives and fatal short-circuitry are involved.
Made of Explodium: The "hard" deaths of Hunters when killed with the fusion gun or explosives, Tank Cyborgs, and the Juggernauts. The first two will damage you if you're close enough, and just run away from the Juggernauts as soon as they start falling. (Juggernauts will kill you unless you have triple shields or slightly below, regardless of difficulty setting. Note also that the Mothers of All Hunters (the gigantic blue ones) will always explode regardless of how you kill them, and usually take away a full shield charge or more if you're too close to them; Mothers of All Cyborgs do likewise).
Malevolent Architecture/No OSHA Compliance: A typical UESC Marathon inhabitant must run through a garbage compactor (as in Defend THIS!), open a door with a Mastermind-style switch puzzle (also in Defend This), then cross walkways with no railings over deadly lava, and then use an elevator which tries to crush you violently before he can get to the toilet.
Jason Jones called "All Roads Lead to Sol", the last level in M2, an “apology” for an “Colony Ship For Sale, Cheap!”, a level from Marathon with a notorious movable platform puzzle, which is by far the most hated moment of the trilogy.
Mars: A lot of backstory involves Mars, its bad relations with Earth, various wars, the breakdown of CRIST mega-freighters that caused the end of a Martian golden age and the beginning of extreme poverty, the first major case of Rampancy courtesy of Traxus IV and, of course, the conversion of Deimos into UESC Marathon.
The Sfierra (named after the Pfhor goddess of lighting and passion), the scout corvette that attacked the UESC Marathon and Tau Ceti, gets rechristened by S'pht as Narhl'Lar, meaning "Freedom and Vengeance". Durandal just calls it Boomer.
The Khfiva, the main ship of Battle Group Three, Western Arm, is renamed as theRozinante
Durandal: Of course, the S'pht wanted to name it "K'liah'Narhl", "Vengeance of K'lia". Whatever.
Menu Time Lockout: Averted in Marathon 2 and Infinity. An enemy might sneak up on you and hit you in the back while you're reading a terminal.
Mind Screw: M1 at times, but Infinity takes a cake.
Mission Control Is Off Its Meds: Durandal in the first game. He stabilized since then, but he and others have occasional moments of this from time to time.
Mission Pack Sequel: Marathon Infinity started out as a set of third-party multiplayer maps for Marathon 2 by Double Aught, who included a few ex-Bungie staff. Marathon 2 probably began as a re-tooling of the Marathon 20/10 Scenario Pack, a canceled Expansion Pack for Marathon.
No Cutscene Inventory Inertia: More of chapter artwork than cutscenes, but those usually show the Security Officer with the Pfhor Shock Staff and a minigun, neither of which is usable by the hero in-game.
No Fair Cheating: If the objective of a level is to reach the exit terminal located in a locked area and you get to it by using a noclip cheat (which didn't even exist in the original version of the games) you will get a message berating you.
Durandal: That's cool how you just walked through that door, but I still won't let you leave.
No-Gear Level: You're captured and stripped of weapons in both "Durandal" and "Infinity".
Noisy Guns: The Assault Rifle dry firing when out of bullets.
Noob Bridge: "Cool Fusion" locks you into a room until you figure out that you can use grenades to toggle switches. Of course, the presence of several packs of grenades (in case you've run out, natch) should be a pretty big clue.
The Durandal level Sorry Don't Make It So is pretty much Pfhor Your Eyes Only from Marathon with an extra area and the new decor. The Game ModRubicon also remixed this level and lampshades it by naming it Not *this* again.
The first level of Infinity, Ne Cede Malis, with its dark, claustrophobic corridors was intentionally designed to invoke memories of the Marathon in general and its first level Arrival in particular, which was similarly designed. Some noted that similarities don't stop at design choices (note that the last of the Infinity screenshots is from Acme Station rather than Ne Cede Malis).
Also, of course, the Vidmaster Challenge levels, ultra-hard versions of what Big Name Fan Randall Shaw (who created them) considered the hardest level from each game. YMMV on whether these were actually the hardest ("Acme Station", for example, is usually considered the hardest level in Infinity, while "Sorry Don't Make It So" is often considered the hardest level from Marathon 2).
"you probably want to waste the last three bullets in the clip before entering Super Mega Carnage Room."
One-Hit Kill: The Running Punch kills Minor Fighters instantly.
One-Hit Polykill: The Shotguns courtesy of classic early FPS physics. (In modern FPS, all of the pellets will hit the intended target; In classic FPS, as soon as the target dies, it for all purposes ceases to exist, and the remaining pellets that haven't reached the dead target will then continue to go behind it)
Oxygen Meter: Unlike in most other games where the rate of air consumption is static, here the rate of consumption increases depending on what you are doing, including getting damaged. It is also worth noting that the player's oxygen meter drains about twice as quickly when the run/swim key is held down, even if the player is just standing still. This is also subject to difficulty levels (harder=less air). None of this is noted anywhere in the documentation for the game, and put together it is one of many reasons why Acme Station level from Infinity, with its very finite oxygen supplies, is so damn hard. To make matters worse, the next level, Post Naval Trauma (a very long level), is also a vacuum level, and the oxygen recharger for the level is only accessible after almost half of the level has been cleared. Before that, you only get two one-time-only recharge canisters.
Another curiosity is that unlike in most games, the meter doesn't recharge by just standing in breathable air. You have to instead find oxygen tanks and wall-mounted rechargers. This can lead to the absurd situation where after almost completely using up your oxygen, you can stay above water for an arbitrarily large amount of time, only to drown instantly upon submerging your head.
Pamphlet Shelf: In the first game, it's very common to run across a lone S'pht hovering in front of a terminal, reading weird nonsense like garbled bits of romance novels and instruction manuals for how to open the doors (intentionally scrambled by Leela to confound the enemy.) In the second game, you get to run around inside Pfhor military outposts and go through their e-mail, most of which is very humble requests, invariably denied, to superior officers for basic necessities like food, water, and safety railingsfor the perilous catwalks.
Parody Commercial: Durandal being silly with fake newspaper ads about selling the Colony Ship/Abandoned Homeworld, cheap. And the AIs looking for cyborg ads.
Privateer: The Nar Privateers in the Durandal epilogue who intercept the Pfhor ship carrying Leela and sell it to Vylae, which then results in Leela going Rampant and taking over their 15-planet network.
Promoted Fanboy: The chapter screens in the 2nd & 3rd titles were the work of Craig Mullins, a Hollywood background painter whose fanart for the first game impressed Bungie sufficiently for them to commission him.
A number of people who worked on Infinity could also be considered Promoted Fanboys, most notably Randy Reddig. The final level, "Aye Mak Sicur", is based on a map Reddig released for the original Marathon entitled "Pfhactory". Randall Shaw and Tuncer Deniz could also be included in this group, although neither of their contributions were as extensive.
Punctuation Shaker: The S'pht'Kr, who lived on the moon K'lia of the planet Lh'owon, orbiting a star containing a W'rkncacnter. Need I go on?
Ragnarok-Proofing: The S'pht stuff on Lh'owon, lampshaded in the terminal by the Pfhor officer who remarks about the thousand-year-old S'pht structures and that their computer network still works.
Rated M for Manly: It's a 90's FPS where you blow away hordes of monsters almost singlehandedly with an absurd amount of firepower. 'Nuff said. Furthermore, a common feat done by skilled Marathoners is to run through a level and kill everything WITH YOUR BARE HANDS!
Reactor Boss: Both of the destroying Durandal's core levels are this in essence.
Sci-Fi Writers Have No Sense of Scale: The first game states that a lightspeed message will take 92 years to reach Earth. In reality, Tau Ceti is only 11.77 lightyears from Earth (one of the reasons why it's so common as an early human colony world in the first place!).
Secondary Fire: Quite a few weapons have them, and if not, it is usually for dual wielding.
In the fan mod Eternal, the Alien gun from the first game returns with the secondary ability to unload half of its ammo to fire a shotgun-like blast.
Second Law My Ass: The very concept of being subservient is an anathema for Rampant AIs.
Sequence Breaking: It's possible to skip several levels in Infinity with clever grenade jumping in the "Electric Sheep" levels. This game is popular with Speed Runners for this reason.
Set a Mook to Kill a Mook: Via Doom-style infighting. With the high enemy numbers and with lots of energy blasts flying around, it barely requires any effort on the player's part. This is one of the very few things that is easier on higher difficulty settings, because most major Pfhor can be "berserked" - when they are near death, they increase speed and ferocity and start attacking anything and everything around them. Naturally, the only Pfhor you encounter on major difficulty settings are major Pfhor. Pfhor and several of their ostensible allies like S'pht, cyborgs, and drones can also be provoked to fight one another if one takes a friendly fire hit from the other - again, this is much more likely to happen on higher difficulty settings. Of course, on the easier settings you probably won't need this to happen in the first place, and the higher difficulty settings are so difficult that you probably won't be able to win the game without mastering this technique.
Short Range Shotgun: Averted, while the sawed-off shotguns are not as accurate as Doom's pump-action shotgun, their effective range is still larger than the usual videogame shotgun.
Shotguns Are Just Better: The shotgun is a pretty basic boomstick. It's not pump-action, it doesn't shoot grenades like the assault rifle or have the raw power of the rocket launcher or flamethrower or the flashy quality of the fusion pistol or the alien gun. It's just a shotgun. But there is something about how ridiculously lethal it is and how you flip the gun (or guns if you're lucky) to reload that make it the coolest weapon in the game.
Also, Durandal states that its reloading mechanism is so sophisticated as to be incomprehensible to the character (and by extension, the player.) Sure, it's a bit of a Hand Wave, but it's a cool and funny one, so let's let 'em get away with it.
Sighted Guns Are Low Tech: Can be averted in Aleph One, though, which adds an option for crosshairs that wasn't present in the original game.
Sigil Spam: The Marathon and Jjaro emblems in the first and third games respectively.
Slave Liberation: The Security Officer destroys the cyborg that mindcontrolled the S'pht, who then immediately start revolting.
Sliding Scale of Robot Intelligence: Normal AIs are Nobel-bot level, while the rampant ones are Deus Est Machina. Also, the whole plot started because Durandal, the Nobel-bot level AI, was assigned to control doors and misc.parts of the ship, the Brick-level tasks, and nothing more. He didn't like that.
Slow Doors: The huge doors in If I Had A Rocket Launcher, I'd Make Someone Pay from the second game, they take a while just to start operating when used, open and close very, very slowly and they open up from the top instead of the bottom, all while the infinite number of Pfhor just keep on coming. Good thing you have the infinite number of ammo lying around, plus the aforementioned Rocket Launcher.
Smart House: UESC Marathon is this run by three AIs: Leela (General Command), Tycho (Science and Engineering) and Durandal (Doors and other mundane stuff, and he really, really didn't like that).
Smoldering Shoes: The hard deaths of power armor wearing VacBoBs leaves behind a single smoldering boot.
Sniper Pistol: Until the addition of SMG, the pistols were your prime sniping weapons.
So Last Season: Durandal's excuse for stripping you of all weapons in the beginning of M2.
The Song of Roland: Several story points are loosely based on the work (for example:Roland/Security Officer trying to break/kill Sword!Durandal/AI!Durandal to prevent its/his capture by the Saracens/Pfhor), and the song itself is mentioned one way or another in all games:
Durandal: Tycho never got it right either, especially the part about Roland breaking me. He couldn't. No one can.
Spot the Imposter: At one point in Durandal you're are charged with rooting out enemy Simulacrum A-BoBs in the allied BoB base. Of course, considering the series' attitude towards BoBs and that the map in which the mission takes place is called God Will Sort The Dead..., you can guess how that turns out.
Standard FPS Guns: The Trilogy mixes up a little since the first game came before the FPS genre was big enough for anything to be standardized:
Emergency Weapon: Fists, more useful thanks to running charge that instantly kills weaker enemies.
Pistol: More mileage due to ability to dualwield and its accuracy.
Automatic Weapon + Grenade Launcher: The first known assault rifle with grenade launcher combo in FPS genre, some would say that the Grenade Launcher is a main weapon while Rifle is for self-defense in close quarters.
Energy Weapon: The Fusion Gun with the ability to charge for more powerful shots, works in vacuum when other weapons don't. Gets an upgrade in the sequels that makes it effective against armored enemies.
Flamethrower: Effective against organic enemies.
Rocket Launcher: Overlaps with BFG, considering its increased power compared to the rocket launchers in other games, and that the planned BFG, the Wave Motion Cannon, was scrapped in development.
Marksman Gun + Gimmicky Weapon: The Alien gun, cannot be reloaded and you have to find another one when runs out of ammo.
Durandal and Infinity uses the above with few changes:
Super Shotgun: Sawed-off shotguns with the rate of fire of the regular shotgun when dualwielded, which is why a second shotgun is a late game weapon, not counting secrets.
Flamethrower + Energy Weapon + Gimmicky Weapon: Replacing the old alien gun, the new alien gun acts like an energy weapon that shoots balls of fire. Still cannot be reloaded.
Marksman Gun: The SMG in Infinity, taking the old alien gun's role.
Story Branching: Marathon was planned to have this based on how many civilians (Bobs) you managed to save, but the idea was dropped (probably because the Bobs are damn hard to keep alive) and the different ending terminal messages praising or criticizing you based on your performance are what's left of the idea. The game engine still had the capability to do it, though, a feature several Game Mods took advantage of, most notably Rubicon.
Stripped to the Bone: The result of killing something with the flamethrower or certain energy weapons. Lava and alien coolant have this effect too.
Stupid Neutral: Thoth. He was built to make sure none of the clans ever fully wiped each other out in their frequent wars.
When Durandal reveals himself to have faked his death in order to trick Thoth into helping humanity, Thoth then allies himself with the Phfor because now they're the side at a disadvantage. It's too little too late, though.
Teleporters and Transporters: Your main method of transportation between levels (and sometimes in levels themselves, too). At first teleportation only works with existing jump pads, but when Durandal gets his hands on Pfhor teleportation technology, the destination coordinates are the only thing required for teleportation. Unfortunately, Rampant AIs just love to teleport people into open space as punishment.
Teleporter Accident: The Pfhor captain in Infinity suffers this by teleporting into vacuum courtesy of Tycho.
Teleport Interdiction: The S'pht Citadel has this in place, forcing the Security Officer to teleport outside on the wrong side of the moat of lava.
That Makes Me Feel Angry: One of the levels in Durandal is named Begging for mercy makes me angry!. In this level Durandal orders you to kill him so that he won't end up like Leela, dissembled and examined by Pfhor scientists (as far as we know). Of course, it is a part of his Plan.
That's No Moon: Inverted, and used quite literally, with two starships that were originally moons. The titular Marathon was constructed from Deimos, and when you are looking for K'lia (the legendary missing moon of Lh'owon) it turns out it's been flying around the galaxy powered by an ancient Jjaro warp drive.
Word of God states that Nar have this in form of literal worldships, and their smallest ships are still larger than most normal battleships.
Theme Naming: This series, Halo, and Destiny are part of one. Durandal, Cortana.. Destiny ups the ante, though—instead of one of the swords, that game features a "War Mind" named Charlemagne—aka the king whose companions wielded Durandal and Cortana. No word on a Joyeuse yet.
The various sections of level "The Rose" in the first game are named after plant parts.
The Infinity chapter names "Despair", "Rage" and "Envy" as synonym for Rampancy stages. Combined with final level Aye Mak Sicur and you get "Dreams".
Melancholy: When the AI realizes its full potential and despairs over its heavily restricted nature.
Anger: When the AI lashes out against everyone and everything in rage over its situation.
Jealousy: When the AI actively tries to free itself of any restrictions and tries to expand itself through computer networks.
Throw Away Guns: The Alien guns, since you have no idea how to reload them and no means to see how much ammo they have, your only option is to use one until it runs dry and find another one.
Thrown Out the Airlock: The Rampant AIs have a bad habit of teleporting everybody they don't like (including our protagonist at times) directly into outer space. And before that, Leela vented one area of UESC Marathon to get rid of the Pfhor, and Durandal vented entire sections of the Pfhor scout ship.
Time Skip: 17 years between Marathon and Durandal.
Too Awesome to Use: The Shotguns and the Rocket Launcher due to scarcity of their ammo, and the latter is mostly saved for the Juggernauts. The level "If I had a Rocket Launcher..." from the second game gives practically unlimited ammo for them to slaughter the Pfhor.
Translator Microbes: The terminal text with alien languages, which are translated with Security Officer's built-in translator, leaving only few words with uncertain meaning.
Turns Red: Tougher variants of the enemies become more aggressive when sufficiently damaged. On the plus side, they are more likely to engage in mook infighting, with the possibility of starting one without the player's help.
Ur Example: For the mouselook control scheme. Quake went onto to be the Trope Codifier due to Marathon being a non-PC game and therefore relatively obscure in mainstream gaming.
The Unfought: With the exception of the Pfhor mindcontrol cyborg, the Security Officer never gets to fight face-to-face with the Big Bads/Bigger Bads of the games.
Unusable Enemy Equipment — You can kill one type of enemy, the Enforcer, in such a way that he'll drop his weapon. Lesser enemies assault you in such great numbers that if the game allowed you to take their guns, you'd probably have more ammo from a single level than you'd need for the entire game.
Unwinnable: A number of “suicide traps” existed, including the Guide Dang It secret rooms on “Smells like Napalm” and “Blaspheme Quarantine.” Even worse were “trap” situations where you could ruin a saved game by having too little health or oxygen to reach the next charge-up.
Another rare but frustrating Unwinnable is when you save your game right when you're about to be killed. There’s also a secret room in “Never Burn Money” that requires grenade jumping to get out of. Needless to say, if you waste all your grenades that could present a bit of a problem.
Cool Fusion is impossible to complete when starting it with the level select code, since you need the AR/grenade launcher to hit the switches to get out of the first room and there isn't one provided here. In this and other levels where you have to shoot switches, you can also get stuck if you for some reason waste your grenades and fusion batteries.
Videogame Cruelty Punishment: Not present in the initial game, but in the sequels if you kill too many BoBs (the amount depends on the difficulty setting) they'll start shooting at you. Many other allies are even more fickle - if you hit any S'pht'Kr or (in the third game) allied Pfhor at all the ones you hit will immediately start firing on you. However, the Oath of the Vidmaster (presented in the skip level dialogue box - command-option-new game on the Mac version, control-shift-new game on the PC version) calls for the mass slaughter of BoBs.
Video Games And Fate: The Security Officer is for all intents and purposes a pawn on the AIs' figurative chessboard, particularly Durandal, who enjoys rubbing it in about the protagonist's lack of freedom while bragging about gaining his. In the second game, Durandal, the Security Officer is hinted to be an Eternal Hero destined to battle evil for all eternity, whatever he likes it or not. And then in the final game, Infinity, the Cosmic Horror screws everything up, and the Security Officer has to take matters into his hands, while going slightly insane in the process somewhat similar to the AI Rampancy, in the end managing to break free from the AIs' control. In the epilogue, moments before the heat death of the Universe, Durandal muses about the Security Officer, and concludes that he is Destiny itself.
Viewers Are Geniuses: The mythology of the Marathon universe is remarkably deep, right up there with LOST and Harry Potter. Fans on the Marathon's Story Page have examined the games' mysteries through the lenses of numerology, mathematics, mythology & religion, Lovecraftian literature, computer science, classic British television, and many more, all in an attempt to piece together the big picture. See also Wild Mass Guessing below.
Voice with an Internet Connection: The AIs don't have bodies or faces, so the only way you can communicate with them is through computer terminals. This gets a little silly when the second game does the same thing with the humans and Pfhor.
Water Is Blue: In Bungie's defense, the Marathon 2 engine was released in 1996, so liquid transparency was out of the question. The Aleph One sourceport adds transparency, though.
We Can Rebuild Him: Mark IV Mjolnir combat cyborgs, referenced in terminals at various points in the game. The lead character is specifically addressed as not entirely human, and in a software glitch is referred to as "Mjolnir Recon 54."
Hint: Durandal is not your father, and you will not join the Dark Side or rule the galaxy together as father and son. Sorry.
What Measure Is a Mook?: The S'pht initially. Infinity ups this when you have to kill specific Pfhors and then Humans.
What the Hell, Player?: If you kill enough allies, the rest of the allies will turn against you. Averted with BoBs, whose deaths are encouraged by the developers themselves.
Wild Mass Guessing: While the original Marathon had a lot of exposition compared to its contemporaries, it also left a lot of questions unanswered. This prompted loads of WMG in the early Marathon fan community which continue to this day. The Marathon's Story Page on popular fansite Bungie.org is a central repository for much of it.
Leela: There are obviously many things which we do not understand, and may never be able to.
This is notable because the developers at Bungie took notice of this, and it informed much of their later story design for the Halo series, intentionally leaving gaps to encourage more WMG. The Marathon's Story page was the first to recieve notification about the game that would be revealed to be Halo in the form of cryptic, in-universe emails to encourage the fans to start speculating among themselves prior to the product's official announcement.
Alternate Universe Fic/Continuation: Infinity heavily implies that the Security Officer is jumping between several timelines to get a Close Enough Timeline and that the final result is not in the same universe as Marathon and Durandal. As a result, many of the fan-made scenarios play with this idea:
Tempus Irae and Phoenix are set after Infinity as the Security Officer and the S'pht fight in the Human-Pfhor War without Durandal.
Rubicon is set after Durandal instead of Infinity. Might be a specific case of Continuation if you accept some of the more flexible theories about what exactly happened in Infinity.
The mod itself references Infinity in the prologue, where one terminal states that the members of Blake's team who got dropped off on Earth each had a different story of what happened. It then goes even further with the final terminal in that sequence, which is done in the style of the dream terminals from Infinity. That terminal ends with the words "All Roads Lead To...", calling back to "All Roads Lead to Sol", the final level of Durandal. Yeah, it's a Mind Screw sequence.
Eternal is set after Infinity, but diverges when S'bthuth and the rest of the S'pht go crazy before the war ends, tipping the scales in Pfhor favor. It begins and ends at the exact same moment in time thanks to Time Travel, and per Word of God is designed so that any game that is a sequel to Infinity can also be a sequel to Eternal (assuming, of course, that it does not contradict Eternal's plot).
In two levels of Operation Vengeance, you pilot a Pfhor Juggernaut.
Author Existence Failure: Sadly, the creator of Pfh'Joueur appears to have died of cancer. Many of the files for her scenario are no longer being hosted as a result of this. This basically means that, unless someone has and posts the missing scripts that enabled the game to run under Aleph One, the game can only be played properly under Mac OS 9, which is a shame, because it's a great scenario.
Bilingual Bonus: The level title "Pfhor får lamm" from Eternal is derived from a common Swedish joke, "Far, får får får? Nej, får får lamm", meaning "Father, do sheep beget sheep? No, sheep beget lambs". "Får" is pronounced basically indistinguishably from "Pfhor".
Bloodstained Glass Windows: Happens a lot in Tempus Irae. There are examples in other games as well, such as "Sanctum Sanctorum" and "Holy Wars" in Phoenix.
Bottomless Pit Rescue Service: Played straight in some scenarios, averted in others. If you fall off a cliff in Phoenix, you die instantly. If you fall into a pit in a certain level of Fell, you get stuck and have to reload.
Breaking the Fourth Wall: At one point in Phoenix a resident crazy AI shows you a series of brackets, which basically serves as a "You are on this level of this mod" info.
Call Back: While the major scenarios generally have entirely different development teams (a few people have worked on multiple scenarios in The Verse), in many cases the creators went to painstaking lengths to make them mutually compatible, to the point where the expansions to the game have a largely shared mythology with very few Plot Holes. Even the architecture styles are often reminiscent of one another - the fact that the Atreides (in Phoenix) looks awfully like the Chimera (in Rubicon) is surely no coincdence. The ending of Phoenix also appears to have been deliberately designed to explain how the player got back into Durandal's service between Infinity and Rubicon.
Collapsing Lair: In EVIL, the Mystics' planet starts to implode after you destroy their time machine. In RED, the Big Bad's spaceship starts exploding after you kill him, and the explosions can kill you in this case.
Continuity Nod: Word of God states that the ending of Eternal is deliberately modelled after the ending of Marathon 2 but taken Up to Eleven. There are plenty of other continuity nods scattered throughout various scenarios for the game; in fact they're usually the rule rather than the exception. In some cases you'll see entire bits of architecture reused from the original games (this is even lampshaded by the level title "Not *this* again..." in Rubicon).
Cross Over: Excalibur: Morgana's Revenge, although set outside the Marathon verse, has a cameo by the Pfhor in one level.
Direct Continuous Levels: Used quite often in mods. Fell does it with Nox Quondam=>The Face Below the Puddles, Vessel in the Depths=>Marooned (after your ship crashes due to sabotage), and Phaedros' Eighth Guest=> How the Stones Were Placed; Evil has Ten Thousand Spoons=>BEER WINE GUNS AMMO PICNIC SUPPLIES and Schmackle=>Life's End; Tempus Irae has You Got Me in a Vendetta Kind of Mood=>...evil so singularly personified and Mt. Vesuvius=>Mt. Vesuvius II: Electric Boogaloo; Rubicon has Breathing Nothing at All=>Canned Air; Pfh'Joueur has Ce'phf'aldea=>In Deep Doo Doo and several cases of levels on the Nor'Haket; Gemini Station has Gemini Station=>Gemini B. In most cases this was due to limitations of the engine forcing the levels to be split up (for example, if the two levels from Gemini Station had been combined they would have had over 1,500 polygons, which was 50% more than the engine could handle at the time the scenario was developed).
Dream Tropes: Employed in Eternal and Rubicon amongst other scenarios. The story in Rubicon's dream levels may or may not be a continuation of the story in Infinity's dream levels. RED has a series of dream flashbacks towards the end of the game.
Drought Level of Doom: Especially common in game mods, such as "All dressed up..." and "Code 42" in EVIL. The latter is basically Acme Station on steroids. Very scarce ammo, only one 1x shield regenerator and oxygen recharger in the central hub area, and it can be a bit of a trek to get back there from the many maze-like sub-areas. At least you have the unlimited ammo Pfhor staff by this point.
Elite Mooks: The Pfhor Mystics in EVIL, described by the S'pht as the "S'pht'kr of the Pfhor". In Phoenix, the Renegade S'pht are mostly elite versions of normal Pfhor, but they also employ even more elite versions beyond that.
Fan Sequel: Generally, Rubicon is considered the actual sequel to the original Trilogy. Most of the other scenarios go their own direction from the Trilogy; some games have more to do with the originals than others. For instance, EVIL and Red are only tangentially related to the events of the originals at all. However, Eternal and Tempus Irae are more directly related to the conclusion of either Durandal or Infinity, and Phoenix takes place between the Trilogy and Rubicon.
Hey, It's That Guy!: The character Ian in Marathon RED will be recognizable as the same Ian from the Web ComicMac Hall. Marathon RED was a mod artist Ian McConville made before starting webcomics, and the character Ian in the game is an Author Avatar.
Hub Level: Used in several mods - the repositories in Tempus Irae, the titular station in Erodrome(where you could actually backtrack to previous areas), the levels on the various AIs' ships in Rubicon, the levels on the Nor'Haket in Pfh'Joueur, etc.
Hybrid Monster: S'pht'Wr in Rubicon, the hybrid of Pfhor and S'pht that were created to replace the now less loyal S'pht compilers.
The player character becomes a hybrid monster in RED.
The Pfhor VacBOBs and Cyborg BO Bs in Return to Marathon.
King Mook: The "bosses" in Excalibur are upgraded Mooks: Mauvair=Sorcerer, Argantan=Cleric, Mordred=Black Knight.
The Jjaro lightsaber in Eternal. In addition to one-hit killing almost everything, they are one of the two weapons able to kill the otherwise invincible Phantasms imported from Pathways into Darkness, with the Wave Motion Gun being the other one.
Phoenix has one as well, and although it's not as powerful as the Eternal saber, it does allow you to use your extra Fusion ammo and become invincible for a bit.
Excalibur: Morgana's Revenge ((in the Aleph One edition)) lets the player have one for a few of the future levels where the player doesn't have access to Excalibur. It's very powerful, albeit lacking the charged ranged secondary attack of the titular Excalibur.
Rubicon has two and Rubicon X has three. The Pfhor plank is undoubtedly the worst (humanity gets overrun with the virus, Dangi board of directors seize control), the Salinger plank is somewhat better (Dangi's Plan is discovered and Lysander is destroyed, though Durandal appears to maintain the knowledge of how to produce the virus as well as the scientists who were performing research on it), while Rubicon X's Tycho plank seems to be the best for humanity as a whole, albeit in a severely Black and Grey Morality manner (once again, Dangi is exposed and Lysander is destroyed, plus the virus appears to be completely destroyed, as well as any knowledge of how to produce it thanks to the eradication of any surviving scientists who worked with it). However, in the last of these the player also destroys Durandal, which many players may regard as regrettable, but the ending level, "Lazarus Ex Machina" (referring to a man resurrected by Jesus), also implies we maintain Durandal's primal pattern. In Rubicon, each ending is the actual end of the game.
Technically, there are six for Eternal, though each of the "bad" endings teleports you to back to the level where you can set things right again after you see what went wrong.
The somewhat obscure scenario Gemini Station has two. As far as I know, it was the first Marathon scenario to do this, though there may have been an even more obscure one that did so sooner. Gemini Station takes yet another approach from the other two in that the bad ending places the player into an Unwinnable situation and forces a suicide. However, the game disallows saving after the divergence (there isn't a very long period before the forced suicide) so you'll just end up at the point where you can set things right.
Red is often regarded as the most difficult of the major total conversions, in addition to being pants-wettingly scary.
Phoenix is also extremely difficult (you will probably have to decrease your usual difficulty setting by at least one level for it to be at all winnable at your current skill level), although it has a pretty erratic difficulty curve at first. It really starts getting difficult when the levels stop giving you fixed recharge points and only give you powerups, and it doesn't really let up at any point after that. (Nearly all the levels of Tempus Irae on Earth have the same mechanic, but they are nowhere near as difficult, mostly owing to the monster physics changes in Phoenix, as well as the Zerg Rush nature of enemy attacks).
Trojan also has a reputation of being very difficult.
"Not *this* again..." in Rubicon, based off of "Pfhor Your Eyes Only" and "Sorry Don't Make It So". Lampshaded by the title.
"S'pht'ia" (based off of "Eat It, Vid Boi!" and "The Hard Stuff Rules...") and "Let Sleeping Gods Die" (based off of "Six Thousand Feet Under") in Eternal. Justified because you are two thousand years in the past of Lh'owon.
Phoenixhas a secret level based off of the first level from Doom 2, of all things.
Tempus Irae: The Lost Levels has a level based off of the map "The Dismal Oubliette" from Quake. Even the physics are changed to make the level more Quake-like.
Frigidman's multiplayer map B'rak Station was turned into a solo level in Siege of Nor'Korh, the predecessor to EVIL.
The first part of Schmackle in EVIL is based on Blaspheme Quarantine.
Return to Marathon was basically a Nostalgia Scenario, in addition to being absolutely terrifying. Too bad it was never finished.
No Warping Zone: The first area in Siege of Nor'Korh is protected by an energy shield that prevents teleportation from outside, so the ammo you start with is all you get, until you find the hidden supplies of stolen ammo, and later, deactivate the shield.
Older and Wiser: post-Infinity Durandal in Eternal, a lot more humble and benevolent than his past sarcastic jerkass self.
At one point in the REDGame Mod, the protagonist is captured by the Big Bad and mutated into a techno-organic being, aka the Reaver, to do his evil bidding, but turns against him shortly after. You gain twice the speed, unlimited ammo, and many weird but powerful weapons.
In EVIL, the protagonist is turned into the AI against his will to help with the war effort, because he is least likely to go Rampant. He goes Rampant anyway and steals a ship with the goal of killing Durandal, Leela and Tycho.
Proud Warrior Race Guy: The Renegade S'pht in Phoenix. Of course, like the local mad AI says, when an entire culture revolves around defeating the foes that are currently beating them up left and right (with the help of the Security Officer, obviously), they really don't take it well, at all.
Reactor Boss: The level "Break the Sword" in Rubicon X. May be a Call Back to the levels "Begging for Mercy Makes Me Angry!" from M2 and "Hang Brain" from M∞, both of which have exactly the same mission: destroying Durandal. However, unlike the two previous levels, "Break the Sword" actually is the final action sequence of the game (unless you count the secret level).
Likewise for "How Big's Your Can?", the finale of RED.
Real Is Brown: The level "Jagermeister's Nightmare" in Marathon RED.
Rise to the Challenge: In the Tempus Irae level "Mt. Vesuvius II: Electric Boogaloo'', you have to escape a volcanic crater that's flooding with lava.
Rule of Seven: Taken to ridiculous extents in Eternal, as a deliberate Shout-Out to the number's prevalence in the original trilogy. You start out with seven packs of fusion ammo, the maximum of any ammo type you can carry below Total Carnage is 49 (7 x 7), the levels in the Jjaro chapter give you seven zero-point modules each, and so on. Most other scenarios incorporate this to at least a certain amount as well (for example, the opening level of Pfh'Joueur is called "Seven Times Seven").
Tempus Irae, which takes place in Renaissance Italy, features breathtaking (for the time) architecture as well as digitized reproductions of Leonardo's paintings. And in a secret level, actual porn.
The main creator of Phoenix, RyokoTK, has made a serious study of architecture, and it shows. It is one of the most visually impressive scenarios created in the engine to date, despite not yet having any hi-res graphics (a future re-release with HD versions of the textures and monsters has not been ruled out).
Eternal,Excalibur: Morgana's Revenge, and Rubicon have their moments as well. Especially in the X releases.
Secret Level: Evil, Tempus Irae, Pfh'Joueur, Phoenix, and Rubicon all have secret levels. Some of them are set in-universe, and others are basically bonus levels.
Sequel Difficulty Spike: Of a sort, and probably not really intentional. Rubicon X apparently wasn't really tested much on difficulties beyond Normal, with the result that the levels that only appear in Rubicon X get really hard on Major Damage or Total Carnage.
Shout-Out: In a later level of Courier 11, you throw a rock at a switch to crush an otherwise-invincible Enforcer expy, just like the Rancor in Return of the Jedi.
Sword Beam: The titular sword in Excalibur: Morgana's Revenge shoots lightning as a secondary attack.
Synthetic Plague: A plot point in Rubicon, where the Mega Corp. plans to unleash it on human planets after UESC defeats the Pfhor empire, then announce that they developed a cure for it and sell it to the government in exchange for more-or-less total control of humanity.
Also becomes part of the plot in the second act of Fell.
Thrown Out the Airlock: You do this to a pair of Enforcers in one level of Tempus Irae, shortly before you yourself get thrown out an airlock by an explosion.
Time Travel: A Major part of Tempus Irae, Morgana's Revenge, and Eternal.
The Eternal mod lets the player use most of the enemies' weapons. The part above about massive ammo drops is partially true. You always have enough shock staffs and havoc rifle ammo, but many players will run out of ammo for the other weapons from time to time (if you try to rely on the shock staff as much as possible, which is quite feasible for the best players even on Total Carnage but will require quite a bit more patience, this is much less likely, however). However, this is probably because the enemies that drop them are significantly rarer than the Fighters and Troopers. (There are two kinds of Enforcers; otherwise you'd probably never run out of ammo for their weapons either).
The Marathon EVIL mod HandWaves the inability to pick up a normal Pfhor staff as a function of some security system that requires Pfhor biology to work. The chance to equip a staff modified so humans can use it was one of the mod's major draws. The custom Pfhor staff in this mod basically never runs out of ammo. (Well, it would after 32,767 shots of either trigger, but no one's ever going to fire that many).
Excalibur: Morgana's Revenge allows the player to collect weapons and ammunition from fallen foes as many of them use the same weaponry the player can.
Unwinnable: Third-party GameMods tend to be worse than the Marathon Trilogy. Examples: The second half of "Life's End" in Marathon EVIL, if you forget to activate the elevator before going down the optional one-way lava river; and the infamous double doors on the EVIL level "Code 42", where if you accidentally hit one of the switches more than once, the door will get permanently stuck, rendering the rest of the level inaccessible. Even worse, you could accidentally save your game in this situation.
Since the Oxygen Meter decreases much faster on Total Carnage difficulty, there may not be enough time to reach an oxygen recharger in certain game mod vacuum/underwater levels if they were not play-tested well enough.
Updated Re-release: Rubicon underwent a drastic revamp when it was finally ported over to the Aleph One engine, including additional and expanded levels and story, heavily updated graphics (taking advantage of the new engine) and an entirely new storyline/"plank" with its own original ending, which is only accessible during a critical point in the gameplay. That last point wasn't even hinted at in the marketing for Rubicon X.
Excalibur: Morgana's Revenge has had three different versions made. The first one was a total conversion for Marathon 1. The second was an extended edition for the Marathon 2/Infinity engine that added in new levels, weapons, music/sound effects, and enemies. The third was the ultimate release for the Aleph One version of the Marathon 2 engine, and added in even more new levels (now with built in Lua scripts and background music), enemies, doubled the number of weapons in game, and even added player-usable vehicles.
Likewise, Marathon Fell 2.0 had a whole new series of story branches added, with the player siding with a different AI (Parael) after the main one (Balapoel) Face Heel Turns, and a virus/biological weapon infecting Pfhor and turning them into gray zombies.
The Verse/Shared Universe: As mentioned above under Call Back, many of the scenarios interlink with one another. Phoenix, Rubicon, and Eternal (and to a lesser extent Tempus Irae, which sort of goes off in its own direction) are particularly notable for this.