There are occasional discrepancies between the description of a planet and what you find on the surface, if it's possible to land there. Nearly every planet you can land on has some amount of life and water, sometimes random birdsong, even when the description is all about how inhospitable it is. Maybe it's most notable in a system which has two planets you can't land on, a mention that they're a rare sight, two garden worlds in the same system, even if they're now uninhabitable. Yet a third you can land on is clearly supporting life, and can't just be handwaved as a park in an environmental dome or something - there are waterfalls and sweeping vistas. If two garden worlds are unusual, what's three?
The Codex entries specifically state that particle beams and energy weapons can't be stopped by kinetic barriers, yet when you get to use them they act much like their ballistic counterparts. The reason for this is threefold: one, Shepard is affected by weapons the same as the enemies; two, Shepard only has one health bar in the second game versus the two in the first game, with the health meter only being shown after barriers have been depleted; and three, Insanity difficulty is scary enough without your enemies' heavy weapons being able to completely ignore your defenses.
Shepard uses the M8-Avenger assault rifle in many cutscenes regardless if you've replaced its use with another weapon, or if your Shepard's character class can even use assault rifles in gameplay. Likewise, Miranda is shown inspecting her Shuriken machine pistol in a cutscene during the Suicide Mission even if you may have replaced it with another sub-machine gun. During the various cutscenes in the Suicide Mission, any character will be shown firing an Avenger, whether or not they normally use it.
Once the Reaper IFF is installed in the Normandy the Collectors track down the ship and kidnap the crew. The thing is, depending on when you decide to go get the IFF there can be a delay of several quests before this happens. This means the Collectors can ambush the Normandy while it's sitting right outside the Citadel. Also if you choose not to awaken Grunt, his capsule will still be on the ship.
Powers in combat don't match what the Codex tells us at all, on account of game balancing:
For ordering a party member to use a tech ability that should fire off a nano-grenade made from their omni-tool's manufacturing module, Shepard needs line of sight on the target, and the attack will instantly land without a projectile traveling the distance. If Shepard uses one of these abilities, the projectile will actually be fired, takes time to reach the target, and can be stopped by obstacles in the way.
According to the codex, biotic talents are divided into three categories, not a list of individual abilities with specific names. The three categories are telekinesis, kinetic fields, and spatial distortion; a biotic will usually have a natural talent for one field, but the classes mix and match. Sentinels have Warp (distortion) and Throw (telekinesis), while Vanguards have telekinetic abilities but don't have Throw.
Biotics are capable of telekinetically lifting targets into the air to become an easy target, or overloading their neural system and permanently damaging their aiming, or freezing an enemy in place. Enemy biotics will never do this because then the player would die (as anyone who played Mass Effect 1 remembers), even though the above describes about half of the biotic abilities in the game. The only exception to this is Charge, used by a boss in Lair of the Shadow Broker, and even then, the boss never directly charges the player.
Minor example in one of the DLC Firewalker missions: Why do we have a time limit on this mission? The planet is cold enough to freeze the Hammerhead's engine. Why is there a limit on how long we can fly in the Hammerhead? The engine will overheat if we push it too long...
And re-embarking onto the Normandy from the surface also somehow enables extra cooling systems in the jump jets so the Hammerhead can fly up into the hangar bay.
When you're on Haestrom during Tali's recruitment mission, it's said your shields will fry. The only one immune to this is Grunt who uses armor. However Jack, Samara, and adept and vanguard Shepard use barriers instead of shields. They can still get fried by the radiation despite not being generated by electronics and instead by the actual being.
Cerberus forks countless billions into Shepard's mission; first by reviving him with Project Lazarus, second by rebuilding the Normandy at twice its size (keep in mind the regular Normandy used to cost as much as 12,000 fighter spacecraft)... but still they won't fork over more than 200,000 credits as your change for the start.
The Illusive Man: I brought you back. It's up to you to do the rest.
When Subject Zero, "Jack," is first revealed to be a petite woman instead of the hulking man our heroes were expecting, she proceeds to use her biotics to demolish four YMIR mechs at once. She cannot pull off this feat in actual gameplay; in fact she can't take too many heavy hits and it's best not to have Jack directly engage even one YMIR for too long. To top it off, her powers in game don't even work on one!
In DLC squadmate Kasumi's loyalty mission you can enter Hock's room by sneaking around the building and killing several guards. When you try to leave guards come to investigate and one of them mentions how they couldn't hear the shots fired over the loud music. The actual music being played is so low that if you have the volume turned down you probably won't even know it's there.
The logic behind Project Overlord in the DLC of the same name will make a lot less sense if done after the Suicide Mission and you decided to destroy the Collector base instead of following the Illusive Man's advice. Same thing with the Lair of the Shadow Broker DLC.
Similarly, one might wonder why the geth are hostile in Overlord if you first acquire Legion and do its loyalty mission, but this is actually a subversion, since said geth are controlled onsite.
Gang Up on the Human: You can be hiding on the opposite side of the room from all of your enemies, doing nothing but regenerating shields, with Jack tossing troopers left and right and Grunt quite literally in their faces, either smashing them in with his fists or blowing them off with his shotgun, and enemies will still ignore them both to try and kill you. Invoked by Harbinger, who orders his troops to FOCUS ON SHEPARD!
Gargle Blaster: In the Dark Star on the Citadel, Shepard can drink a glass of "uncut batarian ale" and "ryncol", the krogan drink of choice. Ryncol does awful things to anyone that isn't krogan, except for Shepard. Then again, Shepard isn't quite human anymore.
Ratch: Ryncol's a local favorite. Don't try to act tough. It'll tear your insides apart. Grunt: He's not joking. Ryncol hits aliens like ground glass.
EDI: Cerberus regulations are clear, Mr. Moreau: Personalization does not include grease on my bridge cameras. Joker: It's just mad that all of its footage of me looks like a dream sequence.
Gay Option: Yeoman Kelly Chambers, although it's not as developed as the other romance options. It doesn't unlock the Paramour achievement, there's no romance scene, and apparently pursuing it doesn't count as cheating on any significant other from the first game (whose picture never gets turned face down, at any rate). And there's another asari, but sleeping with her is averybadidea. However, doing the latter is purely optional.
Get Back Here Boss: Tela Vasir in the Lair of the Shadow Broker DLC. And it is awesome, in a masochistic sort of way. The Vanguard's Charge really is horribly unfair when it'syouwho is on the receiving end. What's more unfair is that her version of Charge doesn't need a target (and she can even use Shockwave so that she and the waves are headed towards you at the same time!), while you're stuck looking around, locking onto a target, and clearing a path before you can even consider Charging an opponent. Though it is also quite awesome to pursue her with your own Charge ability as a Vanguard. Especially once the shields and armors are down.
Giant Space Flea from Nowhere: The Shadow Broker's true identity (a yahg). Not a bad introduction for a new species, but since the Shadow Broker was mentioned (but not seen) in the first game, this can come off as a tad jarring. The dossiers does state that the yahg killed the previous Shadow Broker and took his stuff the same way Liara eventually does — they even give the exact same orders once they replace their predecessors.
Giving Someone the Pointer Finger: If Legion is Shepard's second squadmate during Tali's loyalty mission, a few additional seconds of cutscene-footage are added where Admiral Koris does this to Legion at the very beginning of the trial.
The Hammerhead is nearly a One-Hit-Point Wonder. Good Lord, it wouldn't be quite so frustrating if they'd just let you save at any point during the geth-infested DLC Firewalker missionsnote and if you die you have to start the entire mission over from the beginning.
This also describes Shepard when comparing their ME2 incarnation to their ME1 incarnation. Removing virtually all defensive abilities but making putting up an offensive that much easier does that.
This is also what Tali tells her pet combat drone to do (go for the optics). This is part of a complex series of Shout-Out to Baldur's Gate 2: Tali's drone (Chiktikka Vas Paus) is named after Chiktikka Fastpaws, the raccoon familiar of the Gnomish god Aerie of Baldurs Gate worships (and whom she often mentions when given orders). From the same game, Minsc has a hamster named Boo, and one of his warcry is screaming to Boo to "Go For the Eyes".
Golden Path: Complete all loyalty missions. Purchase Jacob's ship upgrade so Jack isn't lasered to death by an Oculus, Tali's ship upgrade so the drive core won't explode and kill a squad member, and Garrus's ship upgrade so a beam isn't dislodged to impale a squad member to death. Leave for the suicide mission immediately after your crew gets abducted. On the suicide mission, assign Tali, Legion, or Kasumi to be in the duct, Garrus, Miranda, or Jacob to lead fire teams, Samara/Morinth or Jack for the "Biotic Shield", send Mordin or any other "fragile" squadmate (either Jack, Kasumi, or Tali) back with any rescued crew, and leave Grunt, Garrus, and Zaeed behind on the "hold the line" segment for they have the biggest "strength factor" in favor of your team. Grunt, Garrus, and Zaeed have the highest defense scores of 3 (non-loyal) or 4 (loyal), so it's best to leave at least one of them holding the line, preferably two.
Note that it is possible to save everyone even if not all of them are loyal. It's never a good idea to have non-loyal squadmates in 'specialist' roles like fire team leader or biotic shield, or as party members for the final boss fight. On the other hand, it's entirely possible for characters to survive holding the line near the end whether or not they're loyal, especially if you have DLC characters for additional defensive strength.
Good Cop/Bad Cop: When you and Thane are about to interrogate Elias Kelham in Thane's loyalty mission, you get the option of telling Thane which of these he should be (or just playing it by ear). Presumably, Shepard will then be the other, but you can jump off the rails, naturally, and have them both be "bad cop" or "good cop". One Intimidate option involves telling him you're both the good cop, and the real bad cop is waiting outside...
Thane: I say we let him in. Elias doesn't need fingers to talk.
In Archangel's recruitment mission, a batarian merc repairing a gunship lights up when spoken to. The smoke bothers Shepard, who can electrocute him in a Renegade interrupt and make the boss fight much easier.
At the beginning of a planet mission, another batarian merc is seen popping out for a smoke and noticing the shuttle approaching.
Gray and Grey Morality: The decision to either brainwash or kill the "heretic" geth at the end of Legion's loyalty mission.
Guest Star Party Member: Liara in the Lair of the Shadow Broker DLC. She's treated as a full-fledged party member (she replaces one of your companions), and has her own skill set along with Stasis as her loyalty power (which Shepard can learn as a bonus skill). Wilson in the intro level and Dr. Kenson in the Arrival DLC qualify as well.
Guide Dang It: Averted in one major case. If you decide to follow the Prima game guide to the letter, you're in for a rude awakening during the suicide mission. That's because the guide recommends that, after the crew is abducted, and before launching the rescue mission/suicide mission, you spend as much time as you need to finish up missions, recruit members, and mine resources. What the guide doesn't tell you is if you do not start the suicide mission immediately after the crew is abducted, half the crew will die, including Shepard's potential girlfriend Kelly. Worse yet, if you undertake more than 3 missions before entering the Omega 4 Relay, you will lose your entire crew save Dr. Chakwas.
Gunship Rescue: Archangel's recruitment mission, Samara's recruitment mission, and DLC squadmate Kasumi's loyalty mission put you on the side of this trope usually reserved for bad guys.
Guns in Church: Justified, somewhat; you are a Spectre/former Spectre, and numerous events prove that you are not safe from attack anywhere you go (even your own ship), so it makes sense for your party to walk around fully armed and armoured at all times. Unlike the first game, however, you cannot draw your guns outside of combat.
The M-6 Carnifex Hand Cannon. Its damage is miles above your other pistol option, but it has much more kick and a smaller clip.
There is also the DLC M-5 Phalanx, a high-power game pistol. According to the description, it was designed to have as much stopping power as a standard rifle. It's even more useful with a higher clip, damage and accuracy rating.
Happiness in Slavery: "Indentured servitude" on Illium, though the servants are usually treated right and the one slave broker you run into genuinely cares about the quarian she's dealing with. One of the assignments deals with this, and a morally "right" decision isn't clear.
Hard Mode Perks: The Geth Pulse Rifle, which you can only get by completing Tali's recruitment mission on Hardcore or Insanity. It pierces shields easier.
Heel-Face Brainwashing: Legion's loyalty mission, where you have to decide on whether to wipe out the heretic geth or use an indoctrination virus to force them to agree with the geth majority. Granted, the heretics were going to use it on the other geth to make them see their way, but it's a tough moral decision for most players that don't wanna just Kill 'em All.
Heel-Face Turn: For certain values of heel and face. Paragon Shepard inspires Miranda to quit Cerberus and join them in blowing up the Collector Base; the conversation with the Illusive Man includes her if you take her with you in the final fight.
Heel Face Door Slam: Miranda will be inspired to do that regardless of whether she's loyal or not, but a disloyal Miranda will die a few minutes later in the escape.
Hellhole Prison: The Purgatory Prison Ship. Inmates are regularly beaten or spaced as an example to others, and Kuril regularly sells prisoners to those who can pay and want some vigilante justice.
Henchmen Race: The Collectors. Formerly known as Protheans. In turn, they try to use the vorcha to spread a plague on Omega and kill off all non-humans, as you will learn in Mordin's recruitment mission.
The Hero Dies: For most series, this would be a huge twist. Mass Effect? This was literally the first detail revealed about the second game. The fact that the same thing could happen if you royally screwed up the suicide mission was also made clear, both in-game and in much of the promotional material.
Heroic Fire Rescue: In DLC squadmate Zaeed's loyalty mission, Shepard has to choose between running into a burning refinery in order to turn on the fire suppression systems and rescue the workers, or pursue the man Zaeed has wanted revenge on for twenty years and ignore the workers. Choosing to do the former, however, will cost Zaeed's loyalty, unless enough Paragon points have been attained.
Hide Your Lesbians: Unfortunately, despite an already-present sort-ofGay Option in the first game, and an initial promise from BioWare of additional options in the sequel, Mass Effect 2 manages to obscure the possibility of homosexuality quite completely. Even though your relationship with Liara from the first game carries over (provided you romanced her), the closest the sequel comes to actually having a Gay Option is some light flirting with Kelly.
Provided you respond quickly enough to the crew being kidnapped and save Kelly from the Collectors, things can go a little further: after the endgame, you can choose to continue roaming the galaxy. If you've been chatting Kelly up throughout the game, you're able to invite her up to your quarters for a lap dance and a bit of a cuddle.
There is actually a second, more fleshed-out Gay Option. (Sort of.) On Samara's loyalty mission, you can choose to kill Samara and have her daughter Morinth take her place. The fact that you return from a mission with the woman you were supposed to kill is handwaved by explaining that Morinth can perfectly mimic Samara's speech patterns, actions, and powers. Morinth will then show an interest in mating with Shepard, but only after the Suicide Mission. Assuming both characters survive said mission, the player is given the option to take Morinth up on her offer. Doing so will have three unfortunate side effects. First, you'll have to see her creepy sex face, second, you will die from ecstasy overload, and third, you still won't get the Paramour achievement.
High-Altitude Interrogation: During Thane's recruitment mission, Shepard happens upon a poor mook, standing too close to a window, in a skyscraper. Shepard asks about Thane, threatening to throw the guy out the window. Subverted in that the mook doesn't have vital information necessary for you to continue the mission, and a Renegade Shepard knows it.
Shows up in Legion's loyalty mission: The Reaper-worshipping "heretic" geth have developed a virus intended to brainwash the original geth into following the Reapers. You have the option of rewriting the virus and distributing it through the heretics' network, causing them to return to the original geth.
Also apparently a favorite of Garrus Vakarian during his time as Archangel on Omega according to the Shadow Broker's dossier.
Shepard can dish this out with the DLC Collector Assault Rifle, a captured Reaper-derived weapon, which is very effective at killing Collectors. The irony of using the Reaper's own weapons against them is particularly poignant if in the final battle you use this weapon to take down the Humanoid-Reaper.
This is actually a bittersweet Meaningful Echo from a prior conversation, where Mordin mocked Kirrahe's (from Mass Effect 1) habit of using that expression in heroic speeches.
Mordin: Good Captain. Bit of a cloaca, though. Loved his speeches. "Hold the line!" Personally prefer to get job done and go home.
Also in the Arrival DLC, when you discover the Project members have been indoctrinated, you get locked in the room with the Reaper artifact and are forced to hold out as long as possible will Shepard themself comes under the effects of indoctrination. Slightly subverted in that you don't have to hold out until the Reaper artifact reaches full charge - if you don't, you just pass out and move onto the next part of the mission - but you get an achievement if you do. The artifact knocks you out instead if you survive all 5 waves.
Holographic Terminal: All over the place, literally. DLC squadmate Kasumi will actually introduce herself to you using one of these... while she's on an upper balcony watching you talk to the hologram.
Homage: The mission aboard the derelict Reaper is a big one to HP Lovecraft, complete with references to strange geometries and dreaming dead gods.
The geth space station you board during Legion's loyalty mission is just like the interior of a Borg Cube.
The car chase in Lair of the Shadow Broker is extremely similar to the chase from Attack of the Clones.
Hopeless Boss Fight: In the Arrival DLC. You'll get knocked out by the Reaper artifact even if you survive all five waves.
Hospitality for Heroes: Invoked. In Samara's loyalty mission, Shepard can convince a bartender to throw a round of drinks on the house to get Morinth's attention.
Hotter and Sexier: Goes hand-in-hand with the Darker and Edgier nature of the game. While the sex itself is fairly tame, more than half of the crew are available to Shepard (although less than half for each single sex), sex is mentioned much more often, the turian and quarian couple talking about sexual matters, Fornax, the ardat-yakshi, etc.
Huge Holographic Head: In DLC squadmate Kasumi's loyalty mission, Donovan Hock is apparently fond of this mode of communication, and acts appropriately. In the Overlord DLC the eponymous VI also uses this during its boss fight.
Humans Are Special: Subverted. The Reapers have taken a special interest in humans thanks to Shepard, whose actions made them... interested in human DNA, in much the same way the Protheans were interesting fifty thousand years ago.
Played straight in several conversations with Mordin, who explains that one of the things that sets humans apart from other sentient races in the galaxy is their large genetic diversity. (Which is a strange assertion for a scientist to make — particularly in a series that generally features harder science than most video games — as humans aren't particularly genetically diverse, even compared to other Earth animals such as penguins and chimpanzees.)
Mordin: Biotic abilities, intelligence levels. Can look at random asari, krogan, make reasonable guess. Humans too variable to judge.
Samara also feels humans are especially diverse.
Samara: You are more individualistic than any other species I have encountered. If three humans are in a room, there will be six opinions.
Which is actually not handled consistently in-game, since you yourself encounter the fact that three quarians have at least nine opinions, as you will learn in Tali's loyalty mission.
The major twist at the end is that the Collectors have been taking humans and using their liquefied remains to build a Reaper. And they weren't anywhere near done when you finally put a stop to it. This is how all Reapers are made, after all.
I Can't Do This by Myself: The game has Shepard saying this to the Illusive Man when told that Shepard needs to stop the Collectors and that humanity is at war. Shepard replies "If this is a war, I'll need an army. Or a really good team."
The Purgatory Warden who betrays Shepard by ordering them into a cell without any backup present, after allowing Shepard to keep their guns.
If you get Morinth, whatever you do, don't have sex with her. Shep and Morinth even discuss how she kills anyone who has sex with her. She says Shep is probably "different". Shepard's option to turn her down is "No thanks, I'd rather live." Presumably, Bioware assumed most players would try it out of curiosity (or as penance for having recruited her in the first place). Although, in this case, Shepard has already shown the ability to survive things that would take down a normal human (ryncol, the Widow rifle, death...), so one could be justified in thinking it might work. Still a stupid idea, though.
Ill Girl: A quarian in Eternity on Illium expresses irritation with how everyone she dates thinks "Ooh, she's vulnerable, she could get sick!"
The Immodest Orgasm: Heard at one point when Joker neglects to redirect his entertainment to his earpiece.
Impaled with Extreme Prejudice: Not upgrading the Normandy's weapons systems results in a crew member getting impaled by a bulkhead during the trip through the Omega-4 relay. Not long before, the Nonstandard Game Over during Joker's mini mission involves him being impaled by a Scion.
I'm Standing Right Here: Occurs in Mordin's loyalty mission while trying to rile up a sick krogan if Tali is in the party. Interestingly, this is the Paragon dialogue choice; then again, Tali being there is optional:
Shepard: You? I said a badass, not a sick scout whining like a quarian with a tummy-ache! Tali: I'm standing right here!
Not quite, but in one scene (on Omega, if you choose to represent Patriarch and confront his enemies), Shepard seemingly ducks under a stream of fire from a flamethrower to roundhouse kick an armoured krogan in the face.
Pyro mercs. Light you up and lay on the hurt... unless you use Overload or Incinerate on them, or shoot the tank on their back. Pops like a fiery pimple in that case.
Through Zaeed's DLC, you can exact your revenge using the Firestorm heavy weapon.
Indentured Servitude: Ilium practices this, though many (including possibly Shepard) still consider it slavery. Unlike with the batarians the practice is strictly regulated as to the treatment of the indentures, work conditions, what types of work are permitted, and the length of service allowed. There's even agencies that match indentured workers with employers. In one sidequest Shepard encounters a quarian software engineer who ended up selling herself into indenture to cover gambling debts. Shep can talk a computer company's rep into buying the quarian's contract from an indenture agency.
Infallible Babble: Just to see if players were paying attention during Samara's recruitment mission, BioWare snuck a crucial clue about an encounter later in the same mission. When you interrogate him, corrupt volus merchant Pitne For warns you that all Eclipse mercenaries must commit a murder to earn their uniform and that they are all professional killers. Later on, you meet Elnora, an Eclipse sister in full uniform who claims that she has never fired her weapon and that she joined without knowing how bad they all really were. Then a Renegade interrupt pops up.
Good Is Not Dumb: There's also a Paragon solution that likely deals with Elnora just as well.
Infant Immortality: Averted. Not explicit but a good bit of Fridge Horror. In a letter that is sent to you by one of the survivors of the Horizon attack it is mentioned children were abducted as well as adults. Given what happened to the other colonists they are either dead or processed into grey Reaper goo. The latter is terrifying when it happens to adults but the thought of it happening to children is a whole 'nother level of depravity.
The DLC weapon Mattock Assault Rifle, which is semi-automatic with a 16 round clip—and a high fire-rate cap. Meaning, you can put a LOT of damage on target (especially with Incendiary, Warp, or Disruptor ammo) very quickly and accurately. Couple that with the huge damage bonus of Adrenaline Rush, how the ability makes aiming much easier, and a near game-breaking bug in which said skill does not slow down the Mattock's rate of fire, and you'll be bulldozing through enemies faster than you could even with unlimited Cain ammo. Hilariously, the e-mail notification from the Illusive Man lampshades this. The ship's AI EDI was helping review combat data and, to quote. "She suggested we may be overlooking older, proven technologies in an effort to provide you with the state of art. Normally I wouldn't give much credence to the idea, but when an AI criticizes you for loving high-tech, it gives one pause to consider." It's also accurate to the point where it can replace a Sniper Rifle in a lot of circumstances. Its only drawback is the low amount of ammunition you can carry.
The Locust SMG from Kasumi's DLC has the fast fire rate of a sub machine gun, but is also extremely accurate, with a low spray. Equipping it with one of the types of ammo allows it to make quick work of anything lower than a sub-boss.
The DLC weapon Geth Plasma Shotgun. Not only it looks amazing and sounds amazing when it opens but it has two firing modes (normal and charged, Charged mode requires a couple of seconds of charging time and it causes even more damage per shot than the Claymore), it has ridiculous long range and accuracy for a shotgun, slight homing capability and relatively high ammo count. On top of all that it can be charged right before a Biotic Charge, Adrenaline Rush, Tech Armor or Tactical Cloak (hotkey activation required not to automatically release the shot) and released afterward to be coupled with those abilities' bonuses and multipliers for truly devastating effects. Even on Insanity, a single charged shot (with the right damage bonuses) is enough to remove almost any mook's shielding, if not kill them outright.
The Revenant machine gun, once you get the accuracy upgrade for it. Put that Cain heavy weapon away, soldier, you won't be needing it. While you're at it, slap on some Warp ammo so you don't have to fiddle with switching back and forth between special ammunition types. Remember those annoying enemies with biotic barriers?
The M-98 Widow Anti-Materiel sniper rifle. When collapsed, it appears to be a two-and-a-half-foot-long tube. When brought out to use, it extends in a huge sniper rifle. The weapon's info entry says it weighs 39 kilograms and was made to take out vehicles and krogan. A headshot with it and a few applicable bonuses will instant-kill even elite mooks on all but the higher difficulties. The Widow is Awesome but Impractical in-universe, as it's stated that average humans wouldn't be able to fire it without shattering their arms. Fortunately such things don't apply to Shepard.
The DLC heavy weapon Arc Projector is a big help on Insanity difficulty, where all enemies have additional defenses, the most common being shields. One shot from this weapon is enough to burn out all the shields of every mook in a room if they're close enough to each other.
Insistent Terminology: The asari contract broker on Illium insists that they're not slaves, they're indentured servants!
Instant-Win Condition: Some battles simply require you to kill one enemy. None of the others matter, and since you don't get experience for killing things this time around, there's no reason to. Others end once you cross the other side of the area, regardless of how many enemies are left behind you.
Insurmountable Waist-Height Fence: On Haestrom, during Tali's recruitment mission, surmounting a fallen pillar a little taller than Shepard themself requires gathering and applying demolition charges from behind an enemy swarm. Apparently giving a leg up is lost technology by the 22nd century. Shows up in other places, too.
Enemy flashbang grenades cause a temporary afterimage to overlap the screen. Also, getting drunk causes the screen to go blurry and wobble randomly.
When a rocket or other concussive blast goes off near Shepherd, the sound becomes muted for several seconds while your ears recover.
When you're near death, a bunch of red blood and vein-like art is displayed all over the screen, making it very hard to see things like crates and other waist-high objects you can duck behind to get out of the gunfire. Oh, and your sound gets muffled to nearly the point you can't hear anything but a heartbeat.
During Grunt's loyalty mission (his Rite of Passage), every time the Thresher Maw bursts from the ground, the entire screen vibrates, with some of the HUD elements even moving out of frame.
Near the end of the Overlord DLC, the rogue VI will do this a few times with the doors. One instance has you interacting with a green-marked door only to have the other red-marked door open instead; another appears to require a security bypass but will immediately open once you approach. The last of these gags has the green "Open" icon on the door actually move to another door.
Legion is addressed by the names in the subtitles upon your first meeting, then reverts to "geth" the next time you speak.
More specifically, you can find an upgrade for "geth shields" before you ever meet or recruit Legion. It tries to be coy by saying it upgrades "party members who use geth shield technology", but it's hardly fooling anyone.
Also, one of the DLC packs available on the Cerberus Network explicitly notes that it is an alternate costume for Garrus.
There's also one at the beginning. The identity of your rescuers is initially unknown and Jacob makes a big point of telling you that it's Cerberus. Except that each of the five or so computers that you can interact with prior to that point is named something like 'Cerberus Laptop'.
A minor but noticeable one: near the beginning of the mission on board the derelict Reaper, you find a log from the chief researcher, talking about how the crew is nervous and that he shares their sentiments. As the log finishes, the Codex entry for Reaper Indoctrination flashes on screen. People who played the first game would have figured this was the science team's fate before even stepping aboard, but for those who didn't get the hint or know about indoctrination, it's a giant flashing warning sign.
Internet Backdraft: In-universe. In a conversation with Legion, you learn that the geth invoked one by starting a fictional meme to study organic reactions.
Interrupting Meme: Mass Effect fans seem to have trouble posting anything without attracting Harbinger's "ASSUMING DIRECT CONTROL" line.
On Illium, an asari planet, you naturally run across a number of asari/other race couples and the results of such pairings. This includes: a salarian talking with his lover's daughter (by a past salarian lover); an asari who is afraid of commitment with her poetry-spouting krogan boyfriend because she's worried if he may just be after children (you can help her decide on what to do with her relationship); an asari desperately asking someone to find a locket, the one memento left by her human bondmate before he died; and a pair of talking asari where one wonders if the other's ruthlessness may be due to her batarian father (the batarian-asari gets offended at this and angrily proclaims her father was an excellent caretaker).
The salarian Mordin mentions he's been hit on by several other species — as well as the expected asari, turians regard his skin tone as attractive, and a specific type of krogan "sexual deviant" finds the flexibility of salarians (due to the abundance of cartilage in their skeletons) exciting.
The xenophilic pornography magazine "Fornax", produced by humans, was able to upgrade to five-sensory input due to sheer weight of buyers within a year of being produced — as well as asari, the basic issue routinely features both genders of quarians, batarians, drell and... volus. Yes, as in the enviro-suited pig/dwarf aliens. Smaller but dedicated "niche" branches of Fornax include Genit-Elcor and Krogasm. Strangely, turians are not mentioned.
The game vendor on Citadel mentions the existence of pornographic games.
Game Salesman: Those asari-hanar porn games they sell in Shin Akiba are really nasty.
Of the three Paramours for female Shepard, two are aliens — the drell Thane and the turian Garrus. Male Shepard, though, only gets one xeno-romance — the quarian Tali'Zorah.
On Tuchanka, if you kill the Thresher Maw during Grunt's loyalty quest, on your way back to the shuttle EDI will remark that there are several breeding requests for Grunt and one for Shepard. Grunt, of course, thinks this is hilarious. Although it may not exactly be due to the idea of a krogan wanting to breed with Shepard, but that Grunt's requests outnumber theirs.
Intimidating Revenue Service: One of the things Shepard has to do upon returning to the Citadel is go through the intergalactic IRS. Shepard opts instead to fudge the system, because even Spectres can't make the IRS any less painful.
Inventor of the Mundane: If you ask EDI where Cerberus gets funding from, Joker says that the Illusive Man invented the paper clip. EDI helpfully clarifies, "That is a joke."
Ironic Echo: When first reuniting with Liara on Illium, Shepard walks in on her asking a contact if he's "ever faced an asari commando squad before". In Mass Effect 1, Liara's mother, Matriarch Benezia threatens you with this very same line.
Ironic Name (with a twist of Genius Bonus): Cerberus. In Greek mythology, Kerberos was the guardian hound of Hades. His job was to keep the dead in their place. On a less academic note:
Joker: Cerberus... three-headed dog... How come it's only led by one guy?
Invisibility Cloak: Developed by the geth and stolen by Cerberus. The Infiltrator class and Kasumi can use the cloak, one because they're working with Cerberus, the other because she's a master thief.
It Has Been an Honor: A minor instance. Appears in a note left by the security chief of the Hahne-Kedar production facility in a sidequest.
It's a Small World After All: Just about everyone you met in the first game shows up in the second. In a galaxy of a trillion sentients, this is particularly jarring. Especially since in the first game, most of the game plays out in Council space, whereas the second game is primarily set in the Terminus Systems, practically on opposite sides of the galaxy from one another.
It's Personal: As a result of Shepard killing Sovereign in the first game, the Reapers are not only aware of who Shepard is, but now explicitly state that they are going after Shepard directly.
The Reapers' facade of claiming indifference towards Shepard's actions begins to slip in the Arrival DLC.
Shepard: I prefer obscure music. Morinth: How obscure? Shepard: If you've heard of it, it's already too mainstream for me.
Jack of All Stats: The Sentinel class. Moderately good at tech, biotics, and combat (thanks to Tech Armor), but not exceptional at any of them. Sentinels also have no real weaknesses, and can be powerhouses if played well.
Jerk Ass: Many characters more than qualify as this.
Jerkass Has a Point: Allowing Cerberus to claim the Collector Base is the Renegade ending, and most of the Normandy crew will criticize Shepard's decision if they do so. This has caused a bit of a division in the fan base. It's easy to sympathize with the Illusive Man, who although personally untrustworthy, was correct in stating that no additional lives would be lost by sparing the base, and that the hyper-advanced Collector technology could be used to fight the Reapers.
Though the bigoted asari on Illium is mostly just placing resentment on other races and most of her complaints are unfair, she actually manages to make some good points with her complaints; the salarians uplifting the krogan into a race of Blood Knights without thinking of the long-term consequences, turians solving a lot of their problems through violence (the people who died in the First-Contact War can attest to that), and humans acting like they own the galaxy even though they're relatively new additions to the galactic community (this is even more justified if the player got the old Council killed and made Udina into the human councilor, resulting in a council made up entirely of humans governing a galaxy populated by dozens of races).
Jumping Off the Slippery Slope: In Jacob's loyalty mission, his father, Acting-Captain Ronald Taylor, forced his shipwrecked crew to eat the local plant-life, which contained substances that caused mental degradation, and reserved the "clean" food from the ship for the officers. He rationalizes this to the crew that they are the ones who have the technical skill to repair the distress beacon. It takes them a year to fix, so if they hadn't made that choice, all of them would have been reduced to the mental level of children when the food ran out... but then all of the other officers have "accidents" in the space of a week, and he sat on the beacon for nine years, enjoying the company of his female crewmembers until the "clean" food did run out.
Just Friends: On Illium, in the Eternity bar, you bump into a quarian and a turian talking after work. The quarian is complaining about her boyfriend while the turian is clearly smitten and trying to drop hints that he's the right guy for her. Sadly, she doesn't seem to be aware of any of his increasingly desperate hints. He is popularly referred to as "Friend-Zone Turian" on the Internet.
Just Three People: Jedore, the Blue Suns commander on Korlus, is not happy with her troops' inability to kill your squad with their superior numbers.
Jedore: There are three of them! Three! Anything can be killed if you'd just do your damn jobs!
Kangaroo Court: The Admiralty Board of the Migrant Fleet, at least in the case of Tali's trial. Nonetheless, Shepard can get her off the hook in multiple ways.
Kick the Son of a Bitch: A major reason why Shepard's destruction of the colony in Arrival wasn't a bigger deal morally, because it happened to the batarians, who utilize slavery rings and People Farms, among other things. The effect, however, is very much mitigated in the third game when we discover that while the batarian establishment are a bunch of jerkasses, the regular ones actually aren't that bad.
Kill All Humans: The Reapers' goal, along with killing all the other sentient races. Humanity, however, is top of their list owing to Shepard's actions and their decision to use humans for the next generation of Reapers.
Kill 'em All: The worst possible ending. Only Joker and EDI survive.
Kill Him Already: Shepard and various party members can skip the angst and just get on with at several points. Or they can play the angst straight too.
Incendiary ammo is useful for taking down armor and enemies that regenerate health, mainly krogan. Incendiary grenades and the Incinerate power are also available.
Zaeed's DLC adds the M451 Firestorm, a nasty flamethrower. A situational weapon for most characters, unless you're a Vanguard: in that case, it can be the perfect complement for the Vanguard's peculiar wayto deal with hostiles.
This is also how Zaeed ends his loyalty mission, by ejecting a thermal clip on a puddle of gasoline, setting his target on fire.
Kill It with Ice: Similarly, Cryo Ammo, Cryo Blast, and the M622 Avalanche heavy weapon are good for getting enemies to hold still for a few second while you finish pumping rounds into them. Once frozen, Husks shatter instantly, regardless of how much health they have left.
The current Shadow Broker is actually a yahg that the previous Shadow Broker had captured first as a curiosity, and then an agent before it killed him to take his place. Liara upholds the tradition, although her goal was originally to rescue Feron.
Also, on Tuchanka, the krogan scientist Fortack received his title by killing his predecessor.
Klingons Love Shakespeare: Many things about Earth's culture caught the eyes of other races throughout the series, from its religions (turians practicing Zen Buddhism, Confucianism, and Judaism, the latter of which is also practiced by many quarians) to its sports (krogan helping the New York Giants win the Super Bowl) to its literature (Grunt enjoys the works of Ernest Hemingway) to its plays (Mordin performed in a Gilbert and Sullivan musical). And yes, this includes Shakespeare (some ads on the citadel promote an elcor version of Hamlet).
Knight Templar: The asari justicars to a degree, although they can work within their code for a less extreme solution. As a bonus, if you talk to Samara and ask about the justicars, she equates them with human knights errant or Samurai.
Warden Kuril claims to be one, with his extortion methods being needed to maintain the ship while keeping the scum of the galaxy locked up for a cost, but considering how he ends up showing he wants to imprison Shepard and sell them, it really comes across as rather half-hearted.
Knuckle Cracking: Invoked by Shepard to extract information from a volus on Illium. To the surprise of no one, he quickly gives up the info once Shepard made it clear how much they wanted it. The same thing happens to a elcor on Omega.
In the same mission during a car chase, if you are doing badly (colliding with other vehicles), she will remark that it still beats riding in a Mako.
The Rodam Expeditions store on the Citadel has a subtle one on a pattern in the game - there is a human and a turian there discussing whether assault rifles or shotguns are superior, the human prefering an assault rifle while the turian believes he should get a shotgun, and they express interest in joining the Blue Suns. The basic Blue Suns Trooper enemy are assault-rifle toting humans and shotgun-wielding turians.
The Lancer: In the Lair Of The Shadow Broker DLC, Feron becomes Liara's assistant after she becomes the new Broker.
Landfill Beyond the Stars: A justified case, since space travel really is pretty cheap, and the planet (Korlus) is only for spaceships that broke down in the vicinity of a mass relay in the first place.
Large Ham Title: One krogan on Tuchanka has this: Fortack THE LORD HIGH RESEARCHER!
Leaning on the Fourth Wall: An invocation of this trope occurs during one of Shepard's initial conversations with Miranda on the Normandy. Their talk seems simple enough at first, but then Shepard remarks on how Miranda was "designed to be perfect." Sure enough, the commander is leaning on the nearby bulkhead during this scene.
Leitmotif: "The Normandy Reborn", which shows up whenever the Normandy does something incredibly awesome. It also plays during the ending shot of the Reapers headed for the galaxy.
The Illusive Man has one of his own, which plays every time Shepard talks with him. The same leitmotif carries over to the third game as well.
Each squadmate has their own leitmotifs, which play in the background during their recruitment (except for the Cerberus operatives, the DLC characters and Grunt note the background music on the derelict Reaper is actually Legion's theme) and loyalty missions (except for Samara).
Leave the Two Lovebirds Alone: At the end of the Shadow Broker DLC, Feron will volunteer to check the base's systems and excuse himself, along with your other party member (despite the fact that he only just got out of the torture chair).
What about Niftu Cal, the Biotic God, provided you don't take him out gently?
Lethally Expensive: Shepard recruits Tali after rescuing her from an important surveying mission gone south. Tali's entire squad (aside from herself and possibly one other soldier) is lost getting the data, which concerns a star destabilizing much faster than it ought to be.
Tali: That damn data had better be worth it.
Let's Split Up, Gang: Part of the final mission. Whether the "goes horribly wrong" part gets played straight is entirely up to you.
Lightning Bruiser: The Normandy SR-2 when fully upgraded. Being a frigate optimized for stealthy reconnaissance means she's very fast and agile. Your squadmates can add upgraded shields and armor, as well as a main gun reverse-engineered from Sovereign's wreckage. All told, she's a frigate that hits like a dreadnought or better and has defenses to match. That Collector cruiser never knew what hit it.
If you do something to enemies (such as set them on fire), they will let out a scream that goes on for about thirty seconds before they shut up. If you let them live that long.
Assuming control. Shepard, if I must tear you apart, I will. This hurts you. During combat, Boss in Mook ClothingBig Bad Harbinger is painfully able to spray comments about you and your teammates at about the same rate as his weapon.
Ironically, Harbinger's actually got almost 9 full minutes of one-liners recorded for combat dialogue, but the majority of his phrases are only heard very rarely, while the more generic "NEUTRALIZE COMMANDER SHEPARD" types are repeated ad nauseum.
The screams of the VI during the Overlord DLC seems designed to make you jump out of your seat and tear off your headphones. During the trek through the inert geth ship, the designers go out of their way to blurt out the noise at just the right time to scare the crap out of the player—they even lampshade it with a crew log about Halloween.
Also, teammates love wandering into your line of fire and then complaining about it. Thankfully, friendly fire doesn't actually damage them, so it's just an annoying (or occasionally hilarious) sound effect.
Limited Wardrobe: Each of your companions only has one outfit and possible colour variation after their loyalty mission. In situations that warrant it, they get some sort of minimalist breathing apparatus, but no other protection. It can be slightly goofy to see Jack going into near-vacuum almost topless. However, there exists DLC that add a few new outfits for them.
Miranda's loyalty mission: The Prodigal (Luke 15:11-32)
Legion's loyalty mission: A House Divided (Luke 11:17)
Legion's name: "My name is Legion, for we are many." (Mark 5:9, also appears in Luke)
Load-Bearing Boss: Subverted. Most bosses of this kind in both games are usually fought after things have started blowing up, usually as the result of a button you just pushed. So the explosion of the building you're in immediately after the fight has nothing to do with the krogan you just killed. The same goes for the Reaper fetus, but it at least slams against the platforms you're on, causing them to fall.
Loads and Loads of Characters: Assuming you have the "free" (with new purchase of the game) DLC, there are 11 possible party members and one Palette Swap (Morinth replaces Samara if you decided to be an evil bastard in the latter's loyalty mission). And that's not even counting Kasumi Goto, the (temporary) reappearance of Mass Effect 1 squad members, guest party members such as the quarian marine from Tali's recruitment mission, or the numerous recurring NPCs, both good and bad.
Loads and Loads of Loading: Due to the massive player complaints about the first game, the second one no longer tries to disguise its loading behind implausibly slow elevators, but uses obvious loading screens with stylized animations of the transition taking place (airlock, shuttle ride, etc). This would be fine, except the game will wait until the video is finished to start play, regardless of actual loading, and loads tend to be quicker than the video on a PC (replacing the video with a short one is possible to avoid this). Later patches no longer have this problem.
Looks Like Orlok: The vorcha. Seriously, there is nothing good to say about that race.
Losing the Team Spirit: The sequel makes it painfully clear that without Shepard, the crew of the Normandy cannot function and will break apart. The Council actively trying to discredit Shepard probably didn't help, though.
Even those who weren't on the Normandy went through this. Conversations with Jacob, Ken and Gabby reveal they all left the Alliance and joined Cerberus due to the Council discrediting Shepard. In Ken's case, he mentions if he hadn't have left, he'd probably have been court-martialed for gross insubordination because he was very vocal in his support for Shepard.
Any of the upgrades you find during recruitment and loyalty missions. Didn't pick up that shiny new sniper rifle? Sucks to be you. Didn't get that damage upgrade? No dice.
Also used with some promotional items. Three helmet pieces were available with codes on Dr. Pepper bottles, but there were universal codes that people could use to get them instead. As of June 2010, though, these codes no longer work, so some people are unable to get these pieces. The fact that one piece of promotional armor is available as DLC and a promotional weapon also will be means that, hopefully, these items will be able to be purchased later.
Garrus, in an odd sense. If you never recruited him in the first game, you can't romance him.
Speaking of romance, every new romance option in this game is only available in this game. It will carry over to Mass Effect 3 if you start it here, but if you didn't, you can't start a new one with them later.
Love Theme: "Reflections" is heard during moments when Shepherd is getting involved with one of the love interests.
Low Culture, High Tech: The krogan uplift, initiated by the salarians. Mordin equates it to "giving nuclear weapons to cavemen." Incidentally, the krogan had already plunged their homeworld into a nuclear winter even before the salarians uplifted them.
Loyalty Mission: The Trope Namer. Every party member has an optional Side Quest that secures their full loyalty and increases their chances of surviving the Suicide Mission at the end of the game. It also unlocks a snazzy new uniform such that if you successfully complete all of the Loyalty Missions, your crew will go from a Ragtag Band of Misfits to a unified fighting force. It's also possible to invert the trope by failing in specific ways, causing you to lose the loyalty and friendship of previously-die-hard crew members, which can be a real Tear Jerker.
Ludicrous Gibs: Try shooting a flamethrower-toting enemy's fuel tank. Or Overloading it.
Also try to finish off YMIR mechs with a headshot. KABOOM.
Lured Into a Trap: Picking up Subject Zero from the Purgatory prison ship turns into a trap laid by Warden Kuril to imprison Shepard and sell them to the highest bidder. Also happens to you in the Collector ship, an event which is later revealed to be a Batman Gambit (at your expense) by the Illusive Man.
Played with during Kasumi's loyalty mission. Keeping in line with the numerous homages to heist films found in her mission, the object you are sent to steal - a "greybox" containing the memories of her former partner Keiji Okuda - appears to be a straight guffin at first. It contains mysterious data regarding an Aliiance scandal buried in Keiji's memories and everyone, including Shepard, wants to get their hands on this information. However, this trope is subverted in that Kasumi's primary motivation for recovering the greybox is to relive her personal memories with Keiji. Averted most definitely in Mass Effect 3, when its revealed that the greybox contained information on an Alliance black ops raid on a batarian science lab that was studying Reaper tech, which becomes vital to Kasumi's Sidequest.
Played straight during the MSV Strontium MuleSidequest, in which Shepard is sent to recover a "payload" from a ship which has been hijacked by Blue Suns mercenaries. It's never explained just what the payload is, only that Cerberus wants it. When Shepard opens the crate containing the payload, it glows in a fairly obvious Shout-Out to Pulp Fiction.
Made of Explodium: If you finish off an YMIR mech with a headshot, it overloads and explodes like a shot from the Cain heavy weapon. It will take out anything not behind cover, including other YMIR.
Made of Plasticine: Husks. Anything strong enough to knock them off their feet will make them explode. Including rifle butts. Ice attacks such as Cryo Ammo or the Avalanche will shatter them instantly once they freeze.
Male Gaze: Featured prominently in just about every conversation with Miranda. One particularly memorable instance of this is when she asks for your help regarding her sister. When she's done talking, and you're about to choose what to say next, the camera is focused primarily on Miranda's rear in the foreground. It's almost as though the game is encouraging you to take your time in furthering the dialogue.
There's also the pre-mission conversation with Kasumi in "Stolen Memory". If you play as Fem Shep, there's a point where her breasts are prominently in the foreground.
The game seems to cater to Female Gaze as well, as the camera seems to have no qualms with focusing on anyone's ass in those skin-tight uniforms regardless of gender when dialogue is taking place. See also Jacob's romance scene (holy cow, those abs).
Match Maker Quest: You get to run one on Illium to either resolve issues or end things between an asari and her krogan ex-boyfriend. Worth taking just on account of his poetry.
Mathematician's Answer: If and when Shepard reactivates Legion, it mentions that it monitors information put out on the Extranet and public broadcast by organics. Shepard attempts to clarify whether Legion means organics in general or him specifically. The answer he gets? "Yes." Cue a frustrated "Which?", which finally yields "Both."
Justified in that Legion is a Geth, so one would expect a Mathematician's Answer.
Mauve Shirt: Arguably the crew of the second Normandy are mauve shirts, as several are named and carry out conversations among one another about their families, the mission, etc. Depending on the player, it might be further motivation to go after them right away after the Collectors abduct the crew of the Normandy for other reasons than simply getting the best ending.
Mayfly-December Romance: A common trope in the franchise due to the huge differences in life expectancies between races. It is especially important to the asari, since they have both four-digit lifespans and strong cultural expectations to mate with other species. One asari on Illium is having a hard time deciding how to respond to an amorous krogan looking for a committed relationship, since krogan also live for centuries and a relationship would last far longer than with a shorter-lived race.
Cerberus was formed as a result of a perceived need to have an independent group to protect humanity from aliens outside the Charon relay; in Greek Mythology, Cerberus is the guardian of the underworld and Charon is the ferryman for crossing into the Underworld. In addition, Cerberus (the dog) had three heads. Cerberus (the organization) has three divisions: political, scientific, and military.
Illium is an asari-settled and populated planet that is outside of asari territory and serves as a link and trading hub with the lawless and foreign Terminus Systems. Ilium is one of the names of Troy, a Greek-settled and -populated city that was founded outside the territory of Greece itself and served as a link and trading hub with the "lawless" and "barbarian" nations of Asia.
The security mechs' names come from Norse mythology: Loki is the god of fire, Fenris his son, a monstrous wolf, and Ymir, a giant, was the first living being in the Norse creation myth.
A lot of characters. Examples:
Shepard, of course — shepherd.
Grunt is a rather obvious one and decides to adopt the name because it's meaningful to him, so the trope applies in-universe as well.
The way most characters pronounce Solus's name it sounds like "soulless." Before you meet him, a lot of NPCs comment on him, describing him pretty much as a soulless killer.
Miranda is of Latin origin, meaning "worthy of admiration." She sure seems to agree with this meaning. Miranda is also the name of (powerful sorcerer) Prospero's daughter in Shakespeare's The Tempest. Miranda's father is a powerful tycoon.
Then there is the Lazarus Project named for Lazarus, the man whom Jesus brought back from the dead.
However if you don't save the Council she still bitches at you for the nearly 10,000 souls you sacrificed.
Mordin also averts and acknowledges this trope when he calls his favourite nephew — as a scientist who lives by I Did What I Had to Do, he uses this to keep perspective before fighting the Collectors.
Mordin: Hard to imagine galaxy. Too many people. Faceless. Statistics. Easy to depersonalize. Good when doing unpleasant work. For this fight, want personal connection. Can't anthropomorphize galaxy. But can think of favorite nephew. Fighting for him.
Mind Hive: The geth are explained to be this; what we see and fight are merely mobile platforms for hundreds (1,183 in Legion's case) of uploaded runtimes. Individually, these programs are not very intelligent, but they gain sentience and understanding by working together.
If you choose the right dialogue options before the suicide mission, afterwards Legion will reveal that the same is true for the Reapers' "we are each a nation" gig: each Reaper contains the uploaded intellects of uncountable organic lifeforms (likely the very lifeforms that the Reaper is built of). It's suggested that the Reapers select only certain individuals for their unique genetic stock, while the rest of the species is exterminated.
Mirror Chemistry: The quarians and turians are based on right-handed amino-acids, while most other races use left-handed like humans. This is mentioned almost every time you enter a restaurant or bar in a rather obvious example of Expo Speak. You'd think that it wouldn't take long to remember this issue for someone actually living in a multi-racial community. You will hear this again in a lot more detail from Mordin if you romance one of them (Garrus or Tali).
Misaimed Fandom: In-universe example from the Lair of the Shadow Broker DLC. Anderson saw a vid called Saren: A Hero Betrayed — and apparently he needed a lot of alcohol for that.
Missing Trailer Scene: Despite most of the advertising focusing on them as such, Shepard never actually refers to the colonists (or anyone else) as "the lost" in the game.
Money for Nothing: Inverted; there are more things to buy than there are credits to buy them with. Played straight again in subsequent playthroughs or with Mass Effect 1 characters who had several million credits when imported into the second game. Also played straight with minerals: by the time you get enough Element Zero or platinum for all the upgrades, you will likely also have big piles of palladium and iridium, and nothing to do with them.
The part when the Collectors kidnap the Normandy's crew and Joker is temporarily playable is a Player Punch, but it also contains shout outs to The Matrix and Futurama, and one of the most hilarious jokes in the game, all in the space of four seconds.
There's also Tali's trial, which is all very dramatic and serious... until one of the admirals drops those atrocious penis puns.
Due to the way items are acquired in this game, and the fact that Shepard can be rewarded with an item mid-conversation during Tali's loyalty mission, said mission can often end something like this:
Shepard: Come on, Tali'Zorah vas Normandy. Let's get back to our ship. Tali:[quietly] Thank you... Captain. [conversation ends] Shepard:[looking at omni-tool]I'LL TAKE IT!
Korlus turns into this thanks to the Blue Suns' radio chatter. It quickly becomes apparent that Shepard's team of three is a bigger threat than all of Okeer's rejected krogan, their boss is no help whatsoever, and all they can really do is panic.
The Arrival DLC also turns into this. Once Shepard wakes up, a scientist starts freaking out, and once s/he starts slaughtering his/her way through the entire facility, the guards begin panicking as well.
Moral Guardians: The Codex is written by the HSA/Citadel Council. The moment that you realize that Sovereign is recorded as being a geth ship, you realize that the Codex is purposely being rewritten in-universe, presumably to prevent "mass hysteria".
Morality Kitchen Sink: While the first game has this in spades (especially if you're a Renegade), the second game has this extensively, ranging the whole scale from the hero end ("pure" Paragon Shepard), to those in the middle (Garrus, especially during his worst moments), those close to the villain extreme (the Illusive Man), and all the way down to the people like Nassana Dantius and Morinth.
The system in which Jack's mission takes place is called Dakka.
Also, the point of Garrus's ship upgrade.
Supposedly the whole point of the thermal clips and disposable heat sinks. Instead of waiting several seconds for your heat sink to cool down, you eject the heat sink and the clip automatically loads in a new one, allowing you to resume shooting almost immediately. Unfortunately, due to the decision to eliminate cooldown entirely this simply becomes a limited ammo system, effectively resulting inless dakka.
The M-76 Revanant LMG that Soldiers can pick up on the Collector ship has huge clips of very damaging shots, but low accuracy. It actually seems more like a support weapon than anything. This gun can take down a gunship without reloading, but is hard to use against individuals (although if they clump together it will wipe out a group in seconds). Then again, that's what Adrenaline Rush is for.
Mordor: The closest outer space can come to it: the Collectors live in the galactic core, which is full of exploding stars, black holes, and a minefield of hull skeletons of ships that entered it and never returned. Even more inhospitable than space normally is.
Mugging the Monster: Samara's loyalty mission features a turian named Meln in the VIP area of a nightclub who will crassly proposition FemShep if she intervenes to keep him from sexually harassing (and possibly assaulting) an asari dancer. Cue Meln being punched, then thrown in the general direction of the door. And if Shepard is wearing a certain DLC outfit, then this is done by a woman in high heels and a Little Black Dress.
Multiple Endings: Four different endings depending on the decisions you made in the Suicide Mission. If Shepard destroys the Collector hideout, the Illusive Man chews them out for destroying a valuable piece of technology, with Shepard responding in kind. If Shepard preserves the hideout, the Illusive Man praises Shepard instead. In either case, if Shepard dies, Joker takes Shepard's place in the conversation with the Illusive Man. The ending also has minor variations depending on which party members lived or died during the mission.
Mundane Utility: In one of the last Firewalker DLC missions, Shepard discovers a gigantic Prothean sphere that can alter its size, emit energy, and transmit massive amounts of encoded data. Shepard keeps it on their table as an ornament. It makes cool noises when you poke it.
My God, What Have I Done?: One of the admirals on the board during Tali's trial — Admiral Zaal'Koris vas Qwib-Qwib — is a geth apologist, a minority philosophical movement that thinks the quarians should leave their old homeworld to the geth and find a new place to call their own. Why? Because objectively speaking, the entire conflict is the quarians' fault to begin with: when the geth looked to be on the verge of becoming intelligent enough to rebel, the quarians tried to destroy them before it could become an issue — only to discover that they were already smart enough, they just weren't interested in rebelling. The geth then said "Fuck this noise" and kicked the quarians out of the planet like you'd kick out a small but irritating hobonote That's right. The quarians have exactly the same backstory as The Matrix.
Mythology Gag: You can edit what Shepard wears while on board the Normandy. One of these outfits—black pants and a pale brown leather vest—is a direct callback to Canderous Ordo's default outfit in Knights of the Old Republic.
A statue of a Dragon Age Ogre can be seen in Kasumi's loyalty mission.