FridgeBrilliance:
* Before leaving for the hostage mission at the very start of the game, Prichard explains that Jensen's augs will display biomedical data if he's in pain. But the health display on your HUD, even when at maximum health, never fades. Safe to assume, then, that Jensen is in constant pain.
* The ending, in the most unintentional way. Many expressed disappointment at the [[spoiler: press a button ending]]. In real life there's something called [[http://en.wikipedia.org/wiki/Choice_architecture Choice Architecture]] which means the circumstances in which people make decisions can be and generally have been influenced by the actions of others. A video game is inherently an illustration of this. Not only are the paths and outcomes all designed, but developers put incentives and obstacles (items, bonuses, hazards) that make you prefer certain paths to others. In the story you have people [[spoiler: like Sarif, Darrow, and Taggart]] who are much bigger than Adam actively shaping the world, leaving Adam little opportunity to create his own choices, he's forced to make actions within the conditions that result from the ramifications of everyone elses' power and actions. And in real life, we already know that the outcome has been decided because [[VideoGame/DeusEx the sequel]] already exists. We also know the developers had constraints that they faced in developing the ending. What we have is essentially the aggregation of constraint, both ''within'' the story and in the actual ''developing process'' of the story. So the ending makes you come face to face with the truth that all of your choices (and their consequences) have already been designed (because it's a game whose constraints manifest from those the developers faced). And within the story itself it makes you realize that Adam (and Eliza) are constrained to certain choices because there are actors far more powerful than them, whose actions indirectly already influenced what choices would be available to them.

* The fact that Adam's augs are more widespread than strictly mandated by his injuries is actually foreshadowed in the opening cutscene. When Adam meets Namir, he gets tossed through a window, leaving huge splinters in both arms. Despite this, his right arm is usable enough to attempt to shoot Namir and later try and fight him off while still embedded in that machine. Cut to about a minute into the "Getting Augmented" title cutscene. The doctor retorts "Haven't you lost enough people today?", presumably to Sarif, while Adam roars in pain. Look at Adam's body. ''His right arm is missing.''
* The fact that the ending is decided by [[spoiler: a mere button press]] is actually a statement on how technology, and dependence on it, has enabled a few powerful people to have great leverage over the whole world. It also shows how the equivalent of Fox News or CNN can have massive effects on society.
* Having a LIMB clinic in a geoengineering facility in the middle of the ''Arctic Ocean'' looks like GameplayAndStorySegregation at its finest until you remember that Panchaea's construction involved heavy use of augmented workers and thus having an on-site clinic is quite logical. [[FridgeLogic Why there are still ads in the bathrooms, however...]]
** Because they want everyone to blow their paychecks as soon as they get them. See also: American military bases.
** For some reason major corporations seem to always fill their employee-only areas with advertisments, as well.
** The [[WatsonianVersusDoylist Doylist]] explanation is that all the mirrors have ads because reflections are time and resource consuming.
* Eliza starts doubting [[spoiler: her masters]] and fixating on Adam Jensen after being ordered to [[spoiler: disrupt satellite communications temporarily over Detroit]]. Eliza facilitates and manipulates global communications; being ordered to [[spoiler: ''block'' a signal, to not just transmit altered information but to deliberately deny the intended recipient ''any'' information, went directly against what she was created to do.]] Of ''course'' she starts doubting at that point.
* Jensen recharges his augs with energy bars(and the occasional jar of high-energy paste available from LIMB clinics). However, they aren't available from any of the ever-present vending machines, and merchants don't stock them either. He has to [[KleptomaniacHero swipe every one]] - gameplay-wise, this is so he can't spam energy-draining augs, especially the undodgeable takedown moves. The Brilliance is that Brand Name [[http://deusex.wikia.com/wiki/Cyberboost_Proenergy_Bar Cyberboost Proenergy Bars]], "an artificial food energy source, packed with proteins and carbohydrates... 90% fat free with no sugar added" are most likely ''prescription-only'', and may in fact contain small amounts of [[http://deusex.wikia.com/wiki/Neuropozyne Neuropozyne]]. This theory also explains why Jensen can't overcharge his augmentations with conventional food.
** Doesn't the energy aug in the Praxis menu mention you can recharge with regular food? It's a stretch to suggest that ''power bars'' would be sold as a prescription. LIMB sells them because it's a support item for their augments. [[spoiler: Especially since Jensen doesn't ''need'' Neuropozyne.]]
*** Food can ''recharge'' Jensen's augs - one cell worth. Overcharge requires Cyberboost.
* The chaos caused by [[spoiler: Darrow's signal]] would be the perfect catalyst for all the horrible things that happened in the background of the original ''VideoGame/DeusEx''. In the wake of that level of destruction and violence, it would make perfect sense for the tensions leading toward the Northwest War to break out and for Pakistan and India to start tossing nukes back and forth. Those really just needed a proper spark to set off, and [[spoiler: Darrow]] gave them a freaking flamethrower.
** Added to that, if the 4th "no spin" option were canon there would be no one around to even suggest that the temporary spike in violence had any cause related to augmentation manipulation or augmentation failure.
* The fact that the endgame involves [[spoiler: fighting/evading groups of zombie-like madmen]] is actually quite brilliant when one considers that Deus Ex has always been a series about adapting to new circumstances and fighting intelligently. The opponents on [[spoiler: Panchaea]] require a complete shift in your fighting strategy to adapt to. Those who get stuck in their previous rut will have a hard time adapting to the changing circumstances, while those who have been adaptable, flexible, or simply prepared for anything will easily be able to make the shift to dealing with a totally different kind of enemy. Thus, the game rewards either preparation or intelligent flexibility in the final level by tossing out previous gameplay conventions. It's actually quite brilliant.
* David Sarif was born in 1970 according to the Deus Ex Wiki, making him 57 years old at the time of HR. He's also augmented. Which means that the [[spoiler: Sarif ending is [[http://www.youtube.com/watch?v=Vxi7JRJrod4 Electronic Old Men, Running the World. A New Age.]]]]
** On a more serious note [[spoiler:in this game, the Illuminati turn out to be a bunch of rich and influential people who use the Illuminati name as little more than a means to gain funding and whose plan for world domination is brought crashing down by a single dissenting voice. In other words, perhaps Bob Page wasn't being entirely facetious by calling them "A bunch of pretentious old men playing at running the world"...]]
* David is actually brighter than one would expect. After all, when [[spoiler: Darrow triggers his madness-inducing signal]], Sarif is just about [[spoiler: the only augment on Panachaea apparently unaffected]] - which means ''he'' didn't get the [[spoiler: biochip upgrade either, and probably has his augs custom-engineered to dodge anyone trying to muck around with them remotely.]] Sarif is clearly as GenreSavvy as Jensen.
** Same with Malik and Pritchard. The latter even mentions he'd "check something out" before heading for a LIMB Clinic for the upgrade. Clearly he knew something was fishy.
*** Doesn't stop him from sending Jensen off to get one, though. Gee, thanks Pritchard.
*** Well Pritchard does mention he couldn't get to a LIMB clinic due to the riots.
**** And, in all fairness, Adam ''is'' currently out in the field, with people gunning for him. It's not nearly as pressing for Pritchard or Sarif to get one, let alone a chip from their largest competitor. Adam could always get the chip swapped later, if necessary, but right now he can't exactly afford to suddenly lose all his augmentations in the middle of a firefight. [[spoiler:Which, unfortunately, is exactly what happens, but Pritchard couldn't have ''known'' that.]]
* The Yellow/Black color palette most inner-city street-lights are geared towards the yellow-red end of the spectrum because it's cheaper to make lights that won't attract insects that way than to push the light into the more natural-looking blue-green spectrum.
** There's also the fact that Adam is wearing yellow-tinted shades the whole game.
** The main page states: "[...]the yellow represents the rapid advancements and enthusiasm, a willingness to take humanity to new heights, the black representing the conspiracy and chaos of the time." Also? Yellow stands for greed and jealousy and black for the will to do everything right. YEP.
** Another little bit of fridge brilliance relating to the yellow-ness - What is a pale yellow fluid? Amniotic fluid. The entire world is in a womb-like state, the augmentations being the growing and maturing baby. This is the first entry in the series (timeline-wise), so we're at the very beginning of the headlong rush into augmentation.
** Finally, the yellow colour palette ties in with the original Deus Ex. In all three of the original endings, there is night/day symbolism associated with technology. In the Helios ending, [[spoiler:Denton/Helios]] refers to a "dawning of a new day", in the Morgan Everett ending Everett claims that "eventually we will lead them into the day" and the Tracer Tong ending is referred to as a "new dark age". If the endings of the original Deus Ex represent a dawn or a plunge into darkness, Human Revolution, with its yellowy-orange colour palette, represents the sunset beforehand.
* As if Adam didn't need more reasons for hating Hong Lee beyond [[spoiler: his callous murder of the pregnant Evelyn Carmichael over his family's threats of disinheritance]], there is the final nail in the coffin that is [[spoiler:the murder weapon. Who else but an amateur clockmaker like Jensen could possibly despise more someone who would commit murder using an antique clock?]]
** Especially if you're playing a pacifist Jensen, and see his taking up of clockmaking to be, in part, an early attempt to prove to himself that his augments are usful for something other than murder.
* The hidden ending after the credits [[spoiler: shows Bob Page talking about how whatever choice you did doesn't matter. But then, Megan Reed shows up to join them. Now go back and watch the entry cinematic. The whole plot of the game just a sideshow to getting Megan to work for them. No consequences to which choice you made, no real stopping of plans. The whole game was a ShaggyDogStory, and no one even realized.]]
** This also ties into [[WebAnimation/ZeroPunctuation Yahtzee]]'s critique of "[[http://zeropunctuation.wikia.com/wiki/Deus_Ex:_Human_Revolution the Endingtron 3000, a big machine with four huge, conspicuous buttons, each of which gives a different ending. But all four endings are just spliced sequences of stock footage with a voiceover from Adam talking about what an awesome dude he is for making that choice. There's no payoff at all, no glimpse of the world our choice created or what became of the characters, no word on whether your techy support guy ever managed to dislodge that tree branch from up his bum.]]" [[spoiler:There's no payoff because ''none of them produce a different ending.'' No matter which message Jensen chooses to broadcast - or even if Jensen chooses to broadcast one at all - the crisis is widespread enough to justify '''all''' of the FEMA Executive Orders going into effect - '''none of which have term limits!''' '''''Bob Page just conquered the United States!''''' Yahtzee, you've ''seen'' the world Jensen created. In detail. It's called [[VideoGame/DeusEx Deus Ex: The Conspiracy]]. That music after the credits? '''''That's the beginning of the first game!''''']]
* Having purchased the game soundtrack and listened to it more closely, it struck me how sad and mournful many of the themes are and now that I've thought about it, it makes perfect sense. As the events in the game are the first steps towards the dystopian society of [=DX=], the soundtrack is essentially one to the fall of human civilization.
** Yeah, since "It's not the end of the world ... but you can see it from here."
* It always seemed strange that you could find so many important passwords and details in lost Pocket Secretaries, but when you visit TYM headquarters it starts to make some sense. If a large number of corporations in the 2020s start demanding insane limits to how many emails one account can have of course employees are going to desperately transfer all of the vital information they have onto more convenient (if less secure) hand held machines.
* Opening email inboxes to find a maximum message capacity of four... only to have two of those messages be warnings not to expect your maximum message capacity? TruthInTelevision for a lot of people whose work email is handled through Microsoft Outlook who will gleefully spam your inbox with reminders that you're almost out of space.
* Barrett has a gun for an arm. In a [[VideoGame/FinalFantasyVII Square Enix game.]]
* Want yet another subtle clue about how bad the world is? The widespread use of land mines by just about everyone. Normally you'd think of them as just another weapon common to shooting games, but considering that the world has apparently gone from mostly banning them to street gangs, terrorists and private military companies casually using them it's a sign that things have gotten really bad.
* It seems odd that many human revolution augmentations are move advanced than their nanotech counterparts, until you remember than Jensen has half of his body replaced/upgraded with a serious amount of hardware, while the Denton brothers only had to endure a series of injections for their augmentations. Consider the difference between a desktop computer and a smart phone, one has more power but the other has several other advantages.
** How did JC regain power depleted by nanites? He went to a robot, which then recharged on its own and was ready to give him a boost again in about a minute. Mechanical augmentations can do the same thing.
** Jensen's mechanical upgrades had to all be installed at once, so they gave him the most powerful ones available. The Dentons were only really fitted with the basic framework, because they have infinite in-the-field upgrade potential, as and when they need new abilities.
* Throughout the game you can find the occasional Nigerian spam email in various people's mailboxes - the traditional 419 "I am Nigerian royalty scam" - which gives most players a bit of a laugh. There's even one on a top-secret Omega Ranch computer, along with an email from a commander bitching about how their classified machines are still getting spam. But then in Hengsha you can find a storage unit containing a computer that holds three files, one of which is a "Plague intercept" transcribing the conversation the Illuminati were having at the beginning of the game, and another of which is a directory listing. The contents of the directory are a list of terminals that can be found in the game - each one of which has one of the 419 scam emails. The directory name? plague419. ''The scam emails were part of a botnet designed to eavesdrop on the Illuminati'', run out of Hengsha - probably by none other than Tracer Tong.
* [[spoiler:Regardless of points as to whether the first three choices lead to Deus Ex or not, the fourth can easily be seen to lead to it most of all. It wipes out all the major players that would otherwise have been powerful opposition to Page, it creates an enourmous ecological problem plus Tsunamis and most of all it gives the world absolutely no knowledge base regarding a very bad thing that just happened to them. Counter to the stated narration, that's the perfect set-up for manipulation by people not actually on Panchaea, so this all seems like massive Fridge Logic that Jensen would be so utterly stupid.]]
** [[spoiler:Except when you consider everything that Adam Jensen has gone through in the course of the game, starting out at a pretty bad place and getting worse and worse and worse, then add the possibility for all the chances you had to have gone wrong (Malik dying, never saving anyone etc etc) Megan stabbing you in the back and so on and it makes perfect sense for Adam to go with ending four. Not because it's smart, but because he's in the worst possible condition to be making that decision. Which in turn makes it the most dystopian and most likely of all the endings to read forward into Deus Ex.]]
** [[spoiler:Or maybe there is no single canonical ending: UNATCO is formed in reaction to all of the terrorist violence that occurs and is mentioned throughout the game, aug related or not. Corporations become extremely deregulated, which is why Versalife is able to have such a sizable stranglehold on Ambrosia production in the first game, among other advantages, and due to the obvious vulnerabilities of aug killswitches as demonstrated by Darrow, the Illuminati uses the Gray Death as a replacement control scheme. In other words, facets of all endings happen in one form or another. Just like in ''VideoGame/DeusExInvisibleWar'']].
* Why do non-lethal takedowns consume an energy point when really you're just [[{{TapOnTheHead}} punching an enemy out]] or something to that effect? In reality, a single blow to the head generally won't be enough to knock someone unconscious. So when Adam knocks a guard unconscious, he has to use up some of his available energy to boost the strength in his arms. The [[{{BarrierBustingBlow}} "punch through walls"]] augmentation is pretty much the same thing but upgraded so that Adam can channel more power to his arms.
* The title of Sarif Industries is written in a serifed font.
* How computers at the Belltower camp keep getting spam sent to them. The entire system was supposed to be completely free of the internet, but to the commander's confusion and fury it somehow keeps arriving (and possibly even worse if you look at the Fridge Brilliance Nigerian spam entry). Normally you'd think this was strange, but if you check enough emails and personal entries you find out that some of the idiots they hired for security were deliberately downloading animal porn onto the computer of a scientist they didn't like. With that knowledge you realize their computer security is probably less a secure castle and more a house with all the windows and doors left unlocked and open.

FridgeHorror:
* [[spoiler:The Hyron Project is NightmareFuel on its own but there's something that makes it ''even worse'': noticed how the captive women keep screaming that "it's cold"? If you used the social aug at the end of Corporate Warfare, you learn that Hyron was (on paper at least) designed to monitor Panchaea's structural integrity against the shifting pressures of the ''Arctic Ocean''. Are these women literally FEELING the ocean crushing the facility?]]
** [[spoiler: Speaking of Hyron, did you happen to find some of the Panchaea employees' computer passwords? "MSSINGHME", "LSTFORVR", "IWNTLOVE", "FRGOTTN", "YYYYYY". None of the employees chose those passwords. The system assigned them automatically. There are emails from the staff double checking that these passwords are legit and remarking on how creepy they are.]]
* One just hit me after finishing the game a few days ago. Panchaea is a giant station in the Arctic designed to help improve the effects of global warming through iron seeding. Whether it is truely just a massive front for [[spoiler:Darrow's]] plot is not truely seen, but it isn't too far of a stretch to assume that it is a dual-purpose facility given [[spoiler: Darrow's somewhat condescending need to "better humanity"]]. Now, assume you go with the [[spoiler: Destroy Panchaea ending.]] Panchaea is probably one of the most advanced projects helping to reverse global warming, at the very least the biggest. [[spoiler:And Adam just destroyed it completely. The entire facility is crushed under the extreme pressures of the Arctic ocean. Not only does everyone on board (including a ton of innocent workers and both Serif and Taggart with their entourages) drown in the freezing waters of the Arctic, but the foremost attempt to keep the polar caps from melting has just been destroyed. [[NiceJobBreakingItHero Way to flood the rest of the world, Jensen.]] ]]
** According to NPC chatter, Panchaea alone won't cut it anyway. They need five or six more installations like it around the world for the desired effect to come to pass. So it's not absolutely critical factor either way.
*** Confirmed in ''The Missing Link'': you can find a map showing all the necessary Panchea facilities, the one Jensen visits being the only completed one.
** Expanding on a thread from above: Panchaea is huge. It has a significantly large circumference and stretches from sea level all the way down to the sea bed. If you choose [[spoiler: Jensen's ending and destroy Panchaea, you've not only screwed humanity in the long run but more than likely you've created ideal conditions for a ''huge'' tsunami. While it's not outright stated, Panchaea is presumably on the edge of the Pacific ocean, so this tsunami will probably cause incredible destruction to some of the most populated areas in the world, killing thousands if not millions.]]
*** [[FridgeBrilliance What if Panchaea was made mostly of iron?]]
**** [[CompletelyMissingThePoint So what if it was?]] How would [[spoiler:a massive structure crashing down into the sea]] somehow be ''less'' likely [[spoiler:to create a tsunami]] just because it was made of iron?.
***** Oh, it wouldn't. [[spoiler:[[DontExplainTheJoke It's just that Panchaea's purpose was to disperse iron into the ocean, stimulating the phytoplankton growth - in short, iron seeding. So, yeah...]]]]
**** Well, that I knew. [[spoiler:It's just that the possibility of the ruins of Panchaea being used for iron seeding doesn't negate the fact that the collapsing structure would directly cause massive loss of life, and I doubt Adam is thinking as far ahead as 'maybe this thing is made of iron' if he decides to destroy it]]. Adam's intent is obviously not to [[spoiler:end the lives of ''millions'' of people (just, you know, the hundreds or so stuck in Panchaea with him)]], so it's still NiceJobBreakingItHero.
** In VideoGame/DeusEx, [[FridgeBrilliance almost all of South California ended up underwater...]]
*** Yeah, but look at where the Arctic Ocean is on the world map as opposed to California. If Southern California decided to go scuba diving all by its lonesome, nothing that happened in the Arctic Ocean had anything to do with it.
*** The news crawl in the game suggests there's going to be a major earthquake in California in the 2030s.
* In ''The Missing Link'', Doctor Kavanagh mentions that [[spoiler: Megan's research provided a "mutagenic gene combination" that dramatically improves the processes of creating O-C-M "components" (read: Hyron drones).]] Now remember whose genetic structure Megan was researching. [[spoiler: That's right. Adam Jensen helped contribute to the Hyron project.]]
* One passing email you can find in Sarif Industries mentions that "new tissue samples from Patient X have recently become available." Of course, [[spoiler:Adam is Patient X]], and it seems that the "new samples" came from when [[spoiler: Adam was getting augmented]]. That means that [[spoiler: all those hunks of tissue that were removed during Adam's augmentation, including his arms and legs and eyes]] were handed over to Sarif's science team for experimentation.
** ...I think I'm [[NauseaFuel going to be sick]].
*** Arguably this is a good thing, horrifying from a "creepy to feel like being used as a guinea pig" perspective aside. [[spoiler: Since Adam's genetic modification means he doesn't need the drug to accept augmentation, with Sarif working on those samples it means that their goal of eliminating the public need for the drug is within their grasp.]]
*** Doing [[UtopiaJustifiesTheMeans overall good things by incredibly questionable methods]] is more or less Sarif's signature, isn't it?
** I don't think Adam's eyes were replaced, since they look fairly ordinary through the game, plus if they had been he wouldn't nee the [CoolShades].
*** Yes, they were. You can see the artificial elements quite well in the trailer's close-up. They even make a whirring sound as they focus!
* During the "Infiltrate TYM" mission there is nothing keeping Jensen from slaughtering his way through the complex, paying them back by reenacting the prologue raid on Sarif Industries & thereby demonstrating that he's NotSoDifferent after all.
* This troper didn't think much of it during play, but later he realized this: A lot of the people you will fight in this game are not "For the evulz" type mooks. They're mercenaries. People who took the job not to kill, but for money. Money, which in this setting, appears to be somewhat hard to come by. You're not killing evil, death-mongering soldiers who shoot puppies. You're murdering men with families, friends, and people they care for (they may even have the job to care for said people, since they might not have had any other options). And even if you do a totally non-lethal playthrough, some of the takedowns look incredibly painful, and would probably leave them with terrible injuries. Injuries that require medical treatment. Treatment which would probably be very expensive in the future.
** [[JustFollowingOrders Killing for money isn't necessarily preferable to killing for fun]].
*** Killing to make money which will be spent on resources keeping themselves or their loved ones alive/healthy/out of prison.
** ''The Missing Link'' takes care to throw in a lot of lines indicating that not only are most Belltower soldiers not evil and don't know what their company gets up to, but that Belltower is widely seen by soldiers and the general public as an increasingly ''more'' ethical military than national ones. Many of them are actually idealists, much like UNATCO.
* Hugh Darrow is missing an arm but nothing in the game tells you why. However Hugh Darrow is not only the inventor of Augmentation but also one of the few people so screwed by genetics that he can never use them. How did he find this out? After lopping off his own arm in an attempt to use one of the augmentations only to find out (horrifyingly) that his body will always reject it. No wonder he despises Augmented people so much.

FridgeLogic:
* Here's kind of a ToiletHumor one; [[spoiler:Technically, Adam most likely "gave" Megan Reed his "genetic material" on a [[IntercourseWithYou regular basis]]. The legal situation of her using that material to develop the anti-rejection biochip can thus be rendered quite silly. If Jensen said ThereShouldBeALaw involving "giving genetic material" to a woman, things are going to get ridiculous really fast.]]
** You'd think so, but [[spoiler:men IRL have been forced to pay child support to women without authorizing use of their "genetic material". In one 1997 case, [[http://www.supportguidelines.com/articles/art199903.html they had oral, with a condom, and she took it to dispose of]]. The situation is ''already'' ridiculous.]]