Explanations about the true nature of the Maverick virus in the Mega Man X and Mega Man Zero games, as well as the fate of the Guardians at the end of Zero 3, can only be found in the Rockman Zero Complete Works sourcebook. The events of the ELF War and the backstory for the Eight Judges from Zero 3 are similarly only explained in Japanese drama tracks on an OST remastered CD.
The Mega Man Battle Network and Mega Man Star Force series are full of alphanumeric codes that do various things (Number Trader codes for free stuff, compression codes to make NaviCust parts smaller, etc.) You can find some "legitimately", i.e. in-game, but not all. Where are the rest? Japan, of course. They appear in magazines, during anime episodes, and so on. Japanese fans then post them on the net so the rest of us can get them.
There are also manga prequels to the original series as well. These fill in some of the details behind the game's plot. For example, the prequel manga for Mega Man 9 notes why older robots don't have to worry about the expiration date imposition, show the Robot Masters from the first game attempt to stop the rampage of the latest set, and even explains why Mega Man doesn't have a chargeable Mega Buster after five consecutive games with one. As a Continuity Nod, said explanation was given by Dr. Cossack, who was blackmailed by Wily in the fourth game but working for Dr. Light from the fifth game onward.
And in 2012, the Robot Master Field Guide was released, featuring detailed bios on every single RM to date as well as the series' main characters, in an attempt to compile as much supplementary material as possible in oneEnglish manual.
In IV in particular, there are certain bits about the game's plot and storyline that only ever were covered in the official artbook; some have been incorporated into the (presently-ongoing) manga adaptation, some haven't. Of course, all of this plus the two phone-game side-stories are not available outside of Japan and China, so we in the BoF fandom tend to be really grateful for Scanlation...
Betrayal at Krondor tosses the readers a huge bone concerning one of the main characters and clears up viewer confusion concerning Gorath, who has a beard despite being an elf. Apparently the beardedness is explained by him being half-human on his mother's side (which, unfortunately, is just as impossible in Midkemia canon) - something that is not remarked or even hinted at in the game or the novelisation and should have had huge repercussions for him, if true.
Ni No Kuni, a collaboration between the legendary Studio Ghibli and Level-5, is a unique example in that it comes with the manual. Still not impressed? Its over 300 pages long and includes in-game spells, potion recipes, and the like.
Pick a fighting game. Any fighting game. The apparent obligation of having optimal storylines for each character makes it so that plot essentially disappears within the game, but it's all there, just not immediately obvious.
The Street Fighter series is particularly notorious for this, with the most of the characters' backstories being published in Japanese only publications such as game specific special editions of Gamest Magazine or similar strategy guides/sourcebooks such as All About (insert game title/company here). It doesn't help matters that the English localizations of the early Street Fighter II and Alpha games had inaccurate translations (i.e: changing Cammy's past with Bison from subordinate to lover, Akuma being a demon or mass murderer, or the whole "You must defeat Sheng Long to stand a chance" thing, which launched much Fanon). Incidentally this plot doesn't resemble the one in the action movie at all.
Mortal Kombat has an amazingly complex storyline, for example, but you wouldn't know it from playing the game. Not to mention the players don't find out which characters' endings are canon until the next game in the series is released. Mostly the main plot involves someone betraying someone else and trying to conquer the multiverse, only to be betrayed, only for the betrayer to be betrayed, only for the original betrayer taking back his throne, rinsing and repeating. Everything else involves the heroes trying to defeat/free themselves from the current overlord, and being blindsided by the next usurper. This one doesn't resemble the movies at all, either.
Mortal Kombat vs. DC Universe had a one-shot comic that was only included with the special edition release. It expanded on the plot of the game by showing how the two worlds were merged together, and also explained the absence of fan favorites like Johnny Cage and Robin.
The special edition of Marvel vs. Capcom 3 came with a one-shot comic book that tried to weave a more coherent story, since all you really have to go on in the game itself are the intro sequence and the various non-canon endings.
Furthermore, the only way that one can find out the actual names of the Special Attacks for all of the characters is by either reading the instruction manual (which is incomplete as it lacks certain characters) or visiting the aforementioned official website for Super Smash Bros. This is averted for the original Super Smash Bros. (Nintendo 64), however, as animations accompanied by the Special Attack names are briefly shown at intervals when one reads the biographies found in the Data section.
The Rival Schools series simultaneously averts and plays this trope straight. On one hand, the fighting portions of each game have introductions, cutscenes and endings that (for the most part) explain what's going on and the motivations behind most of the characters' actions; on the other, the Japan-only character creation modes in each game actually reveals even more background info about each character, as well as little known facets of their personalities (though none of it is required to understand the story). If you only play the games in English, you'd never guess Gentle Giant Boman is a fan of sunbathing, or Musical Assassin Yurika can identify a person by the sound of their footsteps.
This is the only way you find out anything about the plot in the Virtua Fighter series, because there isn't even so much as an ending in the games. Although, come back in about a year, you may be enlitened.
Guilty Gear... o lawd, Guilty Gear. Japanese-only drama CD's, Bibles/Material collections and novels and press kits are a few of the things you'll need to get all the plot of the GG universe, especially most anything about the Crusades themselves or the inner workings of the Assassin's Guild.
Spiritual SuccessorBlazBlue has started down this path with a prequel novel explaining what half the cast was up to before the first game started along with more time-travel shenanigans.
Rayman 3: Hoodlum Havoc contained several secrets that were only explained in the manual provided, making it a literal example of this trope.
Additionally, the game uses its manual in-game to break the fourth wall during the opening level by having the character Murphy instruct Rayman by reading to him from the game's manual, occasionally commenting on the manual's various illogicalities.
At one point, the manual actually talks back!
The English release of the Galaxy Angel manga includes an actual manual detailing things that the writer left out from the game.
Batman: Arkham City has a series of comic book minis filling in the gap between itself and its predecessor, Arkham Asylum. The comics detailed how characters like Catwoman came to be captured and show events only alluded to in the game, such as Selina's past encounter with Poison Ivy. They also provided origins for a few of the game's original characters.
Malicious, this popular Download-only Title for PS3 is known for its great gameplay experience and colorful design, the main game is almost devoid of any sort of storytelling, typical of a download-only title you just pick your character up and go on to fight epic battles; that is, if you skip over the conviniently named "Backstory" menu on the Title Screen, in it there is a short novel detailing all of the game's backstory, everything that gives a meaning for what you do in the main game.
A companion volume to the Wild ARMS series reveals that, appearances to the contrary, they actually are directly related to each other — large time gaps and Filgaia's remarkable disaster-proneness obfuscates this, making most of the games appear to be largely unrelated stand-alone titles.
Really common in early (before the mid-80s, approximately) video games. With low resolution and limited storage space, most games would give you no on-screen clues about what to do or why you were doing it. Even worse, many of them had manuals "translated" from Japanese by simply playing the game and making up a new story, leading to some fun confusion when sequels (on later systems with on-screen story) follow the Japanese plot, not the US plot.
Many plot-heavy early games (I.E.: RPGs) had literal 'all there in the manual' plots. Partially as an anti-piracy measure, partially to save space on the cassette/floppy, the game would instruct you to read specific lengthy snippets from its manual upon having reached certain points in the game.
Western text-only computer games used passages from the manual for anti-piracy, but the Infocom games often included toy-like extras to the game. Most were for amusement or to flesh out an idea in the game, but occasionally something, such as a map, would contain very important information.
On the other hand, nearly all of the second-generation (SCI) and third-generation (SCIV) Sierra games that don't have actual copy protection claim, right at the start, that you need "information from the manual" to complete the game, whereas in fact that isn't true. In some cases you do need information from the hint line, though.
While it's not critical to playing the games (other than for the Copy Protection), the King's Quest manuals have massive amounts of Back Story and character notes. The Peter Spear player's guide cranks it Up to Eleven with a creation myth for the universe the series is set in, documents "written" by the characters, and a fictional history of Daventry. And that's not even touching the Fanon on the universe...
The manual for Sid Meier games, particularly the original Pirates, are loaded with historically-accurate details about the era you're playing, including Silver Train and Treasure Fleet routes, information on known pirates of the era, detailed notes on the cities, and commentary on the accuracy (or lack thereof) of the era's firearms! Pirates! used the historical data(ironically) an anti-piracy technique. In the first game, you were asked about the routes of the Treasure Fleet and Silver Trains when arriving in port. In Pirates Gold, in your first confrontation with another ship, you would be shown a flag and asked to identify the famous pirate that it belonged to. These pirates, and their flags, were only ever shown in the manual. In either game, if you answer incorrectly, the game quickly becomes Unwinnable as you will never find any other ships at sea.
The HD rerelease Kingdom Hearts 1.5 HD Re MIX includes the Final Mx content form the first game. A simultaneous release is rumored for North America as well which means that the Final Mix content may be available for the first time outside Japan. It can be assumed that a second collection might do the same for the Final Mix content of the second game and possibly Birth By Sleep as well if it should be included in another collection.
In an odd surprise from Square Enix, Re: Chain of Memories was released in North America in December 2008 (but not in Europe, because Square-Enix really hates Europe). For the unaware, this is a remake of said GBA game, but on the PS2, and in Japan it came bundled with the Updated Re-release of KHII.
358/2 Days is pretty bad in this regard. While it's clearly intended for existing KH fans longing for backstory elaboration, anyone who just picked this up not knowing any better is going to be absolutely lost, as you need to at least understand what is going on in 3 separate games to make sense of the plot: the original Kingdom Hearts, Chain of Memories and KHII. It doesn't stop there, though: the Chambers of Repose and Waking, plot points introduced only in Final Mix+, are mentioned several times, and Ventus from Birth By Sleep makes an Early-Bird Cameo.
Square Enix's "Ultimania" series. These monstrous manuals easily contain a hundred pages for a short book. Most of them are suitably doorstoppers and are packed with all of the information anyone could ever want about the game and its storyline. Unfortunately, it's all in Japanese so it is up to the kindness of fan translators for this information to be shared for a broader audience.
On a similar note, the Reunion Files book is essentially Ultimania for FFVII: Advent Children. It further explains several plot elements, such as who the Remnants are and the fact that they're actually inadvertently undertaking Sephiroth's will, amongst other things. Mercifully, it's in both Japanese and English, and a lot more is covered in the more readily-available Advent Children Complete, but it's still annoying that it's only conventionally available in Japan.
In reality, it seems they packed so much information into the Ultimania Guides that they completely change the tone and course of the original story. Whether it makes the story more sensible or awkward is up to the reader, though none is allowed to question its canon level. Annoyingly enough for some people.
In The Elder Scrolls games you have to dig around through in game supplemental material to make sense of the setting and the plot. Some fans have assembled an online archive of the game supplemental material.
Daggerfall's manual has a 'history' portion that details not only the history that can be found in-game, but also elaborates in more detail the events that lead from meeting the Emperor to waking up in a cave than what the game, itself, does. The manual also includes a handy genealogical chart for the three main noble houses of the Iliac Bay, although that information can be found in-game (just not graphically and in one place). Daggerfall's manual, however, is also notoriously shaky. Because they wrote the manual for features they had in planning, but never got around to release, the manual gives reference to objects which don't exist.
Touhou, and how. While the series has an unusually high amount of dialogue and cutscenes for a shmup, that's really not saying much. Most actual information is in the character profiles, short stories, fanbooks, or spinoff manga.
One word: Dragon. It's the single most powerful being in Gensokyo and the Border which defines Gensokyo won't exist without its approval, but in-game it's only ever alluded to in Iku's lines (of whom she's a messenger). It's getting even more egregious because the kappa is a race that as a whole revere the Dragon, yet Nitori (your kappa ally) never speaks of it in-game.
Some of the side material managed to do this to itself. More specifically, the side-story Bougetsushou was split into three parts: the main story, Silent Sinner in Blue; a collection of character-focused vignettes, Cage in Lunatic Runagate; and a gag-manga, Inaba of the Earth and Inaba of the Moon. Inaba isn't really important to anything, but Runagate explains a few things that were glossed over in Silent Sinner. Also, it has the ending, and the explanation for why the whole thing happens that comes with it.
This is made glaringly obvious when certain characters or subplots become relevant to the main storyline, and suddenly some fully-developed characters will show up in World of Warcraft without their full backstory being given. Half of the story in the Sunwell Plateau dungeon, covering the adventures of Anveena Teague and Kalecgos, is only found in Warcraft: The Sunwell Trilogy, a manga series released several years before the dungeon. Anyone who did the dungeon without reading the book saw a few conversations between Kalecgos and a girl in a bubble who loved him without knowing that Anveena is the human embodiment of the energy of the destroyed Sunwell. It is why her "explosion" helps end the encounter.
The entirety of the Nerubian race's political system, motivations, and personality is found outside the game. In the game there's only one with a speaking part, and it's just about a quest like any other npc.
Ditto as for why people are supposed to invade the Obsidian Sanctum, a sacred place to the black dragons where there is supposed to be no conflict, and kill a dragon who's defending a clutch of eggs. This is because they're twilight dragon eggs, and their presence indicates that the dragon Deathwing is working against the other dragonflights. The red dragonflight is using you as a proxy because they can't directly confront the black dragonflight about it. But the dungeon just showed up after a patch without any of this explanation.
The Dungeon Journal often reveals details about bosses that don't come up in the game, particularly for those that don't appear in Expanded Universe works. For example, Asira Dawnslayer's entry reveals that she was a mercenary who worked for the Twilight Hammer Cult, then was slowly corrupted until she changed her name from Sunbright to Dawnslayer.
Perhaps the most egregious example is the return of King Varian Wrynn. To sum up, since the game was first released, there had always been a long and involved questline involving finding out what happened to the missing king. This quest line cut off suddenly at around level 30 with the capture of someone that might have some information, and a letter to the player saying that they would be called on again when the prisoner divulged his information. Fast-forward several years and the quest line was slightly expanded, only to dead-end again with no real conclusion. In Wrath of the Lich King, the king was suddenly back with (from the perspective of someone who doesn't follow the Expanded Universe) no explanation whatsoever. Why? Because they literally took a quest that had been left dangling in-game for four years and concluded it in the comic book series, in which the missing king is the main character.
Another good example comes in the form of the third expansion to the game, Cataclysm. Quite literally overnight, the whole world was altered completely. The leader of the Horde was suddenly Garrosh Hellscream instead of Thrall, Cairne Bloodhoof was Killed Off for Real and replaced by his son, Baine, and Magni Bronzebeard was effectively killed off and replaced by a council of three, including one of the Always Chaotic Evil Dark Iron clan. Little of this is ever actually explained in-game, and all of it takes place in the novel The Shattering.
Around this time, FandralStaghelm, the widely hated archdruid of the Alliance, suddenly gets replaced, and an early quest in Mount Hyjal in Cataclysm involves escorting him from his prison to prevent the Twilight Hammer cultists from breaking him out. The reason why he was imprisoned is revealed in Stormrage; Xavius manipulated him into corrupting Teldrassil by using an image of his dead son, and when the image vanished and he essentially lost his son again, Fandral lost his sanity.
It gets even more complicated when including the RPG sourcebooks as legitimate sources of information. At least one piece of information is totally inaccurate (the death of Maiev in the sourcebooks was rendered obsolete when she showed up in Outland as a major plot point). This calls into question any assumption made based on the sourcebooks.
Thankfully (or maybe not) a Q&A on the World of Warcraft forums revealed that the sourcebooks are officially not canon.
Starcraft's manual contained much of the game backstory, much of which play a hand in the expansion pack's story (which barely contained any information in its manual, if it existed). The game itself assumes the player is already familiar with the histories and factions of the different races given there. There is no in-game exposition for even basic things, like who the Sons of Korhol or the Xel'Naga are or the Protoss caste system, which are all vital to even vaguely understanding the plot.
The manual also explains why the Zerg need resources to build units.
Starcraft II turned the phenomenon up to eleven; all of the major characters, excepting those retained from the original, have backstories which are only explored in tie-in novels, though a brief summary of each character can be found on the official website.
And most of the fun facts about the units, such as calling the medivac ship a "heal bus" and the subsequent amusing response had by the pilot, can only be found by buying those units in the single player mode and reading the information in the armory.
This would have been the case with Starcraft: Ghost, had it not been cancelled after the novel Starcraft: Ghost: Nova came out, detailing Nova's background and how she came to be a Ghost (she happens to be the most powerful human telepath/telekinetic ever, able to mind-control others and emit TK blasts comparable to nukes; even Zerg!Kerrigan can't match her). Interestingly, the end of the novel has Nova joining the Ghost program, knowing that her memories will be erased, which kinda makes the novel irrelevant. The character of Nova is "revived" and used in Starcraft II, and an additional novel has been written about her exploits.
Diablo's manual contained most of the plot and backstories of all the races and units. This includes a very vivid description of a little boy being transformed into Diablo.
The Halo series has several examples, to the point where you should probably seethis and/or this for all the details.
Halo 2 ends at the start of an epic battle. Halo 3 starts at the end of the same epic battle. The battle itself is covered in the comic series Halo: Uprising.
Even more so, Halo: Combat Evolved begins with the characters having just discovered the titular installation. What happened before that is covered in Halo: The Fall of Reach. Another novel, Halo: The Flood, tells us what everyone else (both human and Covenant) was doing on the ring while the Chief was running around, while Halo: First Strike explains what happened between the first and second games (like how Johnson survived and how the surviving Halo 1 cast got back to Earth).
If you want to know the true reason why the Covenant declared war against humanity, you'll have to read Halo: Contact Harvest.
Halo: Reach is notorious for this: the significance of Dr. Halsey, why she distrusts NOBLE Team, the Forerunner artifact, Cortana, the Pillar of Autumn, and even the setting won't make full sense unless you've not only played the first game, but read the 2010/2011 The Fall of Reach reprint, Halo: Ghosts of Onyx, Halsey's Journal (which only came with the Limited/Legendary edition of the game), this in-universe communication on Bungie's official website, and the Waypoint Data Drops, in order to settle what might otherwise seem to be Halo: Reach's contradictions with earlier Expanded Universe material.
All of that is nothing compared with Halo 4; numerous players who were not familiar with the Kilo-Five trilogy, The Forerunner Saga, and/or the terminals from Halo 3 and 4 expressed severe confusion about the story, ranging from why the Chief is fighting the Elites again to the very identity of the Librarian and the Didact.
Fire Emblem: Path of Radiance and its sequel Radiant Dawn had its backstory explained at the official Japanese website for the series, namely that Lehran and Altina founded Begnion together and they were the first couple to bear a Branded child.
This information could be found in game if the player was willing to go through the game a second time while performing certain extra tasks, but said tasks border on Guide Dang It.
Fire Emblem Awakening has an extensive background site in Japanese that provides many extra details about the world or characters, such as that Gangrel knew Aversa was a Dragon with an Agenda all along, and that Valm is indeed the same continent as Valentia from Fire Emblem Gaiden, and was named after its founder Alm, the hero of that game.
Metal Gear Solid 2 also featured a fictional novel titled In The Darkness of Shadow Moses: The Unofficial Truth, a tell all account written by Nastasha Romanenko exposing the true events of the Shadow Moses Incident from her perspective. This novel elaborates a lot on the Shadow Moses Incident from the support group's end.
Although it is heavily implied in Metal Gear Solid 3: Snake Eater, the Metal Gear Solid 4 Database is also the only place you'll find a direct confirmation that Ocelot is the son of The Boss and The Sorrow. The Metal Gear Solid 4 Database also elaborated on what happened with the Metal Gear Gs as well as the history of Shadow Moses.
The Metal Gear Solid 4 Database is has received some criticism for not resolving some things, getting some info wrong, and retconning some things.
The Japanese manual for the MSX2 version of Metal Gear included bios and artworks of the main characters and bosses (including an explanation of Schneider's motive for creating the resistance movement), and gave the specifications of TX-55 Metal Gear as well as the designs for it. A fan translated version can be viewed here. In contrast, the English manual for the European MSX2 version only included the standard playing instructions, although it's not as bad as the English translated version of the NES port's manual, which pretty much butchered the story.
The Metal Gear 2: Solid Snake manual also elaborated quite a bit on the game's story and other things, and was absolutely vital to playing the game and understanding the story (in fact, it was even needed for a certain part of the game that probably made it far too difficult to be beaten otherwise). For instance, it elaborated on exactly how Solid Snake managed to infiltrate Zanzibarland, the history of Zanzibar Land as well as its statistics, including military strength and natural resources, a history of FOXHOUND, and bios for the main characters. It also explained a bit about the landmarks of Zanzibar Land, and the backstories of several bosses, and specifications of several vehicles encountered in the game, including the Goliath tanks, which were originally supposed to be fought as a boss but were removed due to time constraints and kept as part of the scenery on the first floor of Zanzibar Building, the Hind Ds, which explained that these were modified, the Gigant, and the Sikorsky Dragoon (the chopper that was briefly seen in the ending of the game that took out a platoon of Zanzibar Land personnel when Snake and Holly White were surrounded due to running out of ammo.). Like its predecessor, it gave the statistics of Metal Gear D, as well as elaborated on the mass production of Metal Gear G that Dr. Drago Pettrovich Madnar alluded to in game. It also explained how to use tap codes in this game, which makes the manual absolutely necessary to use to get Dr. Madnar's frequency, and thus get further into the game. A fan translated version can be view here.
There was also a leaked voice casting document for Metal Gear Solid 3: Snake Eater that elaborated on some details on the main characters. It gave the real name of Major Zero (David Oh), and elaborated on a few things about some characters, such as mentioning that the American colleague of Granin was actually Otacon's father (which was later confirmed by Metal Gear Solid: Peace Walker).
The originalMetal Gear Solid included a segment where Kenneth Baker tells Solid Snake that the only way to contact Meryl Silverburgh is to look at back of the "CD case" to find out what her frequency. This is a reference to an actual screenshot on the back of the game's boxart, which depicts Snake conversing with the character in question via Codec.
Microcosm apparently takes place on another world in the distant future, involves a multi-generation war between MegaCorps, an assassination attempt, and Cyberpunkish corporate espionage. You wouldn't know this from playing the game. It's a Rail Shooter with controls that makes Baby Jesus cry himself to sleep at night, and an opening FMV that is almost as long as The Godfather II but explains NOTHING about the labyrinthine story. The manual's story lasts for more than twenty pages, including a three or four chapter story, an atlas of the fictional future star system it takes place in, and an long essay on why the MegaCorps are fighting and how crappy their planet is. All this for a rail shooter that would have to be as bad as Superman 64 to be run-of-the-mill.
Mass Effect seems to be heading this way. The available in-game Codex offers incredibly detailed information on everything from asari biology to element zero. In addition, the two novels offer and expand upon the backstory and provide additional information.
The comic book series Mass Effect: Redemption (an official prequel to Mass Effect 2) explains Liara's attempts to get Shepard's body back from the Shadow Broker in much greater detail, and how she first met Feron. The DLC "Lair of the Shadow Broker" references, but doesn't fully explain, the events mentioned in the comic series.
One tie-in novel, Retribution, finally explains fully one of the major mysteries of the second game: why are the Reapers converting humans into a Reaper? The answer: because organic life is short and imperfect, the Reapers think they're doing us a favor by granting us an immortal existence as one of them.
Valkyrie Profile has the Japanese-only Materials Collection, which contains tons of information about characters and settings. Since the game series is not as popular as, say, Final Fantasy, it has not been translated.
As it is, Killer7 is undoubtedly one of the most bizarre video games ever created, so naturally the developers put out a companion book, Hand in Killer7, that provides some backstory and explanation to the game's characters and events. Though this information is hardly any less confusing than that provided by the game itself, and often outright contradicts the game altogether. Given the nature of the game, this has to be deliberate.
Also, to understand who the characters are (especially some of the characters not in cut scenes, like Coyote and Con) you have to read the manual with the game. It's also nigh IMPOSSIBLE to solve some of the puzzles without this information.
Let's not forget the 12 issue comic miniseries meant to portray the story in a more linear, comprehensible fashion...a miniseries that got to issue four before being summarily canceled. Only one other issue was released, a zero issue, but that one only existed as a promotional material and couldn't be bought on its own.
Homeworld has a large manual which describes the history and technology of your faction leading into the campaign, and goes into quite a bit of detail. However, the intro cutscene usefully summarizes the parts which are directly important.
The sequel, Homeworld: Cataclysm, also provides a long, detailed backstory in the manual, along with descriptions of all of your ships and a lot of enemy ships. Again, though, the really important backstory is summarized in game.
Homeworld 2 plays this straight, though. To really understand the backstory and what's going on, you need to either have shelled out $20 for the strategy guide or waited until the developers released their internal history documents onto the web.
Made worse if you played Cataclysm, since it takes a few missions to realize none of the world-building from that game was canon. Even disregarding that, the material now available still doesn't explain how the Bentusi were reduced to one ship.
One defenseless ship, which was able to destroy entire fleets by itself in the manual. Cataclysm also shows us Bentusi tradeships that can hold off flotillas.
The original version of LucasArts' Loom included a 30-minute introduction on an audio cassette. However, if you've got a pirated version lacking the cassette, you can play the game without missing much.
Also fits if you legally download the game off Steam, or anywhere else.
Suikoden IV's final boss is actually quite an appropriate end to the game, seeing as it's the ultimate source of all Rune Cannon ammunition, and its presence at Fort El-Eal was what allowed the Kooluk to make their giant Rune Cannon superweapon. Its destruction also means that no more Rune Cannons may be made, which is undeniably a Good Thing given how much trouble they've caused. Of course, since this is never addressed in the actual game, if you never read the backstory for the game, which is published separately, it just looks like a Giant Space Flea from Nowhere.
Bust A Groove, a little-known rhythm game for the PSX, was a game entirely about having dance battles with people ranging from twelve year olds and disco playboys to a thirty-foot tall robot and twin aliens. The game itself offers absolutely no explanation for these battles, or the characters themselves for that matter. The manual reveals that the characters are battling one another in order to receive their heart's desire using Dance Power. These wishes are vaguely alluded to in each character's ending cinematic, but never stated outright due to ever character being a Silent Protagonist.
The sequel has the same problem, though it's compounded by the fact that not even the booklet describes the game's plot, just each character's backstory.
The real name of the protagonist of Star Wars: The Force Unleashed is never given in the video game; he is for the most part referred to by his Code Name, "Starkiller", which many fans erroneously assumed to be his real name. The novelization based on the game, however, gives his real name as Galen Marek.
American McGee's Alice, in the deluxe addition, comes coupled with an illustrated "casebook" of Alice from the insane asylum she's staying in. It gives many details about the causes of particular events in the corrupted Wonderland, as well as giving hints about proper ways to defeat certain enemies and bosses.
In The World Ends with You, only the Japanese manual refers to the fact that the abilities of every Player is tied to at least one pin. Yes, this means that Mr. Mew is controlled (partially) via pin (it's called Groove Pawn, by the way).
Shiki does make an off comment about being impressed with Neku's ability to use more than one pin near the start of the game though...
Bad or hasty localization can also cause this. The Nintendo GameCube version of Ikaruga only had the basic story outlined in the manual. Everything else was supposedly in game... but it was removed and not even the Japanese remains. Granted, you'd be lucky to even read half of it before it disappeared, but at least it was there in the other versions.
Sid Meier’s Alpha Centauri has this in spades. Additional information on the faction leaders' personalities, the backstory of the game before arriving on Planet, trivia on the planet and the solar system of Alpha Centauri...you name it.
Psychonauts only recently got a complementary, developer-made Wiki, which you can find here. It also quenches some of the fan speculation, such as revealing the name of Razputin's father (Augustus, for you fanfic writers) and confirming the long fan speculation that Raz' last name is Aquato.
Parodying this trope, the manual of Sub Terra contains a backstory that is not found in the actual game, but is also completely unrelated and irrelevant.
Illwinter strategy game Dominions 3 has a massive 300 some-odd page manual including a complete list of the hundreds of spells and a description and sample strategy for all of the myriad nations, alongside the admittedly limited backstory to the game.
And that still doesn't include stats for most of the national units, details on many unit attributes and spell effects, province stats, etc.
A certain code in StarTropics was revealed only by following an in-game character's cryptic suggestion to dip a certain document in water... the aforementioned document being an actual real document packaged with the game. Without the code, you can't progress. When it hit the Virtual Console, the loading screen showed the letter and code.
Venerable Amiga / DOS adult (pixel art boobs and gore) RPG DreamWeb originally came with the "Diary of a (Mad?) Man", which greatly fleshed out the main character, his mental problems, and the world he lives in. In fact, the story of the diary is far more detailed than the game itself; it also features a progressive rendering of symbol seen in dreams, necessary to unlock one of the final doors.
Although Sword of the Stars gives you a fairly comprehensive info-dump on the in-game universe inside the game, reading the supplementary novel and following the game's forum provides a wealth of supplementary material: The game's story writer is a sci-fi novelist, and likes to frequent the game's forum to answer fluff questions from the fans.
Think you've found a plot hole in one of Kinoko Nasu's visual novels? Well... you may be right. But it's just as likely that Nasu has addressed that very point somewhere, though maybe not in the same route or even the same game. There are so many rules to Nasu's universe that even hardcore fans have trouble keeping them straight.
The first game opens with a title narration saying "Emergency Order: Defeat the Metroid of the planet Zebeth and destroy the Mother Brain the mechanical life vein. Galactic Federal Police M510." You'd have to read the manual to know why the Metroids have to be destroyed.
Super Metroid gave Samus two undocumented moves: the wall jump and the shinespark (no, not that one). These moves aren't in the manual; instead, they're in the demos, and there are also a bunch of animals who demonstrate them for you (of course, this doesn't tell you what buttons to press). Since then, all the 2D games have included these moves — and maintained the tradition of not documenting them.
Super Metroid actually had a third secret move seen only in the demo: the Crystal Flash, a last-ditch recovery technique. The conditions and method for performing this one are so specific that only Nintendo Power readers had a chance of learning it.
Ridley, The Dragon who appears in almost every game, is an extremely intelligent and cunning, if bloodthirsty, military leader. Not that you would know this just by playing the games, as all he's ever done is screech, roar, and claw at Samus whenever he shows up. Further, the way he keeps coming back after being defeated (eating corpses and then absorbing their biomass to heal injuries), is never mentioned outside the manga.
Flashback came with a short comic book explaining the story. The key details are given in the second level, with a few minor characters and events missing.
Action 52 came with a 12-page comic book explaining the origins of the Cheetahmen. The Action 52 manual, however, was quite inaccurate (it appears the game summaries were based on projections rather than the final product). It did offer a mailing form you could fill out to get more complete instructions on each particular game, but they haven't been discovered or even documented on the internet.
The Dark Forces Saga's backstory for the protagonist was first given in the manual for the original game and was later contradicted by a trilogy of graphic novels. It was later revealed in an RPG supplement that the original manual were lies written by the agent who recruited him to make him seem more trustworthy.
The instruction book for the original Teenage Mutant Ninja TurtlesNES game states that the Turtles' main mission in the game is to capture Shredder's Retromutagen Ray generator Life Transformer Gun, with which they can turn Splinter back to a human. This is why, at the end of the game, Splinter is restored to his human form; the game itself makes no mention of the transforming gun.
Shredder can use the gun to One-Hit Kill you in the final battle, but the reason why the turtles want it from him is never explained.
Looking at a whole other type of Splinter, the Splinter Cell games have a metric crapload of extra stuff ranging from novels ("Created by" Tom Clancy, with a negligible amount of help from his two sub-writers, their four ghost-writers, and the four ghost-writers 8 different ghost-writing-agencies), secret-filled flash-websites, trailers, teasers, articles, spinoff-games, multiplayer campaigns(!), etc. The third game in the series was somewhat notorious for explaining the story (namely the manslaughter/murder of Sam's daughter, his short career in crime, subsequent imprisonment and the undercover infiltration of JBA. solely through preview articles and trailers.
The Sierra adventure game Rama was (loosely) based on Arthur C. Clarke's second Rama novel. Despite there being some fairly major differences between the game and the novel, characters in the game will sometimes reference events that only happened in the book.
Zelda II: The Adventure of Link had a rather standard Save the Princess plot in its opening crawl. The manual, however, revealed that the princess you were saving was actually the current princess' distant ancestor who had been put into an eternal sleep because she wouldn't reveal the location of the third Triforce piece to her brother and an evil wizard. It also explained that this is the reason the princess is always named Zelda — in honor of the one under the spell.
Oddly enough, the intro in the English version almost implied that it was the same Zelda from the first game, whereas the Japanese version clearly specifies (in badly translated English) that it's "Another Princess Zelda". The Nintendo Power preview of the game also implied that it was the same Zelda.
Supplementary materials also reveal that the boss of Maze Palace is the evil wizard who cast the sleeping spell on Zelda.
A mild example, but the blond Kokiri in The Legend of Zelda: Ocarina of Time was named "Fado" on an old version of the official site. She's one of the few named Kokiri in the games, a leftover from her important status in the beta.
There is now Hyrule Historia, an encylopedia of sorts for the Zelda mythos in honor of it's twenty-fifth anniversary, which confirms or expounds on a lot of story details that were either ambiguous or outright overlooked in the series. Most notably (and to much controversy), it finally gives an official timeline of all the games to date. The book is basically the answer to every possible question that fans have regarding the series, the characters, and the timelines.
Super Robot Wars does this occasionally, but subverts it with Original Generation Gaiden, which takes most of the "Manual" from the Drama CD and OAV and puts it right in the game.
Then it goes on to use it with it's own Drama CD, which brings us to...
Ace Combat has details not covered in the game proper, such as the stories of the aces as found in the Assault Records or the full history of the Ulysses asteroid.
Sins of a Solar Empire does not have a campaign mode, and as such, you get no storyline with the exception of the opening cinematic.
Machines opens with you aparently playing as a computer. It turns out took over a thousand years to get to this point. Why is explained in print
The SimEarthmanual was over 500 pages, bound in a ring, and was larger than most modern game boxes. It explains the entire philosophy of the game as a "computer toy", the science behind the various models, and the equations for the atmospheric model are ALL IN THE MANUAL. It's quite impressive, but looking back, it was a bit of a wallbanger when they put CO2's greenhouse effect so high, practically ignoring the warming effects of nitrogen, oxygen, and water vapor, despite their completely saturated warming bands.
The various Sim X game manuals LOVED to provide massive amounts of information on the subject they were simulating. SimAnt 's manual was a couple of hundred pages long, but only 20-30 of those pages were about how to play the game; the rest of it was a small introductory textbook to the field of Myrmecology.
SimCity 2000 was much the same. A good chunk of manual, and many times more pages devoted to discussing city planning in reality. Much of it was useful to the game, giving you insight into the models used to create the simulation. Just as much of it was simply a love letter to city planning as a subject of research.
Several significant plot points in the Wing Commander series are, for various reasons, only mentioned in the game manuals. The manual for the X Box Live Arcade game Arena, "Star*Soldier", fleshes out the game in a way the then-limit of 50MB on game size didn't allow. (The limit was bumped to 150MB while Arena was in development.)
Outpost 2 was an early RTS with very sparse cutscenes, so at first glance, the backstory and campaign mission briefings seem sparse- more an Excuse Plot than anything else. Then you crack open the manual or on-disk manual and find detailed explanations of every unit, structure, and weapon, complete with a [very] short story centered around the structure, unit, or weapon, as well as plenty of backstory. Then you realize the game came with a novella on the CD as well, spinning two very different tales (one for each faction, which are very different) about the ongoing struggle to survive. Plymouth's ending in particular comes out of nowhere if you haven't been reading. If you're paying atention, the information (including the corresponding chapter of the novella) also appears in the campaign mode's mission briefings.
Almost all of the powerup names in the Backyard Sports series nowadays come from the manuals for the respective games.
Normally, the mostly-textless opening cutscene of Stretch Panic is utterly confusing and makes no sense. But with the multiple pages of story in the manual, it becomes...very confusing, making little sense. Given that it's a Treasure game, though, that's par for the course.
Also, the same novelization explains the origin of his powers: He made a pact with Satan to gain control of hellspawn to conquer the world. It also explained that he gained control of Hell because of his disposing of Satan.
Both the original System Shock and the sequel has some backstory, while not essential to know, that fleshes out the game more, particularly in the sequel, which explained the motivations of Captain Diego, Korenchkin and Delacroix for joining the Von Braun mission.
A lot of things that seem to come way, way out of left field in Vampire: The Masquerade – Bloodlines are actually taken from the various Old World of Darkness source books. To the point where fans of the tabletop game will appreciate the many references, and everyone else blinks and tries to work out what the hell is up with the freakin' wereshark!
The PC game Where In The USA Is Carmen Sandiego? required you to look up information in Fodor's USA travel guide to get promoted. This was before the internet was in common use, so if you didn't have the book (which came with a new copy of the game), you'd have to guess what the largest export of New Mexico just happened to be.
The obscure adventure game The Eidolon came with a long and detailed story in its manual/diary, full of Steam Punk science and dream logic. It also told you flat-out how to face down certain creatures by detailing the writer's experiences with them. The game itself just starts up in the pilot seat of an unidentified vehicle with nothing but blackness visible.
In the game Vexx, you have to collect a certain number of hearts in order to come to new worlds, one of these hearts is hidden inside a chest (which is itself inside a sort of whale), this chest has a lock on it that you can only open by inserting the right code by pressing buttons. It's possible to guess the right combination, but it becomes much easier with a hint in the manual, the description for the heart even tells you to "look in the book".
The web material for the John Woo game Stranglehold includes bios for all the major characters, such as the Captain with his authoritarian father, Jerry Ying and his estrangement from his straitlaced cop father, Dapang's background in child labor and underground death matches, and the bad guys' various criminal backgrounds. It also includes a tie-in to Hard Boiled, the movie this game is a sequel to, in Mr. James Wong's background, which mentions the involvement of his only son, Johnny, in arms running and his subsequent death in a certain hospital shootout.
In Final Fantasy XIII, much of the story (and various commonly used terms) make no sense unless you read through Datalog. However, it's better than most examples here, because it's conveniently located in-game.
Some - especially critics such as Spoony and Yahtzee, who both made a point of addressing this directly - would say it's actually worse than most of these examples. Instead of expanding on the universe or filling in plot holes, the datalog in Final Fantasy XIII basically has to be read if you want to understand even the most fundamental things about the setting, plot, and motivations of the characters. Needless to say, it's Final Fantasy, so this is a controversial viewpoint. Yahtzee puts this best:
Yahtzee: You're supposed to weave exposition into the narrative, not hand the audience a fucking glossary as they walk in to theatre!
The first two Star Control games feature manuals with lengthy stories explaining the background of the Hierarchy Wars, each race's history, and what happened leading up to the beginning of Star Control II. In the case of the first game, it was arguably an Excuse Plot for a space strategy/combat game, in the case of the second game, most of the relevant information was available in-game if you ask enough of the right questions. And many vital plot points are only in the game, without the manual knowing anything about them.
The various ghouls and player characters from The Ghouls' Forest series of Doommods, as well as the multiplayer Ghouls Vs Humans, used to have detailed bios available on the author's blog. They were then removed (and no known copies exist) because the author felt they were "no longer needed".
The Myst franchise had three novels written with it, the first two of which explain all the background of Atrus, his family, and the D'ni civilization. The third fills in some of the gaps between Riven and Myst 3: Exile.
Played quite literally in Hotel Mario, where Mario turns to the camera in the opening cutscene and tells the player to consult the included instruction manual should they need any help.
In Super Mario Bros. 2, the text on the opening screen tells you that "Wart hates vegetables". This is the key to defeating Wart (the Final Boss); you have to grab vegetables and force-feed them to him.
Most of the (official) Super Mario Bros. games play this straight, where the functions of various characters, enemies, and items are only covered in their instructions manuals, but for some reason Super Mario Galaxy inverts this (although still played straight with Mario's side of the story).
And speaking of Galaxy, there's the game's tie-in trading card game. What makes the trading card game count is the fact that it revealed in the game's prologue the Magikoopa that attacked Mario when he is trying to save Peach when Bowser kidnaps her and carries her high up into space to be... Kamek!
A lot of Satoru's past in Remember11 is explained more thoroughly in a timeline that was released after the game.
Lampshaded in Empire Earth's fourth mission of the Russian campaign when the briefing recommends you to check out the manual to learn more on cybers' abilities.
Humongous Entertainment included help files with every single one of their games, and gave the solutions to all the puzzles.
Each Escape Velocity had more in the manual than the predecessor: the original game was not this trope at all, Override has a couple of things that were never explicitly stated in-game, and Nova has eight 'preamble' PDFs, one of which is a Universe Chronology, six of which go into deeper detail about the importantnote That is, each corresponds to one of the major and exclusive to one another storylines of the game civilizations and groups of the 'verse, and one which is an example of a traditional song sung by one minor group.
In the first Shenmue every single character, from Ryo to Nozomi to the guys who exist only to get beaten up in the 70 Man Fight, has their own name and backstory, most of them fairly detailed and interesting. Did you know that the girl working outside the thrift shop is really the daughter of a wealthy family who ran away to escape an arranged marriage? Or that the reason Nozomi is in love with Ryo is due to him defending her from bullies? Unless you've gone out of your way to search for the bios most likely not.
Much of the backstory in NieR is kept in the supplementary book Grimoire Nier, including the game's connection to Drakengard and the beginnings of Project Gestalt.
The Reconstruction, sort of. There's an in-game glossary that has background information and history on tons of things, some of which are part of the plot that the game itself only half-explains to you. Fortunately, though, none of it is really vital to understanding the actual plot.
The plot of Shatterhand isn't really stated at all in the game proper.
The NES version of Hydlide had an opening screen in which a demon casts a spell and turns a princess into three fairies. The full explanation of this was left to the manual. The PC-88 version at least had a screen of text at the beginning of the game.
There's tons of this in Asura's Wrath, which can be found in the pre order art book and all the extras in the game menu, such as where the Demi-Gods come from, how they came to be, the time period the gohma started attacking, explaining the origins of Mantra and how it became a power source, and several other things for stuff that is unexplained in the already fleshed out story of the main game.
Even inFAMOUS got in on this trope. In between the first and second game there was an interquel comic published and released by DC. Although the main story was still understandable enough without reading the comic, a number of the game's subplots are only resolved in said comic, like Cole coming to forgive Zeke, whatever happened to Sasha, Alden, and Moya, and Zeke learning that Kessler is Cole's future self.
Most of the plots for the Angry Birds series games are all covered in their commercials.
The notorious 1985 flop The Great Space Race for the ZX Spectrum came with the back-story for every character in a series of comic strips (which actually looked like first-drafts drawn with marker pen) in the manual. This kind of thing was common in the 8-bit era as memory and cassette/disk space was limited and traditional media was often used to provide background and atmosphere for game worlds.
Golden Sun's instruction booklet came with notes on everyone's relationships to one another, and a map of the continent you would be exploring. A similar cheat sheet came with The Lost Age, which in addition to helping you keep tabs of your adventure, helped newcomers who hadn't played the first game catch up on what was going on.
However, Dark Dawn is by far the biggest offender in the series. In addition to the map and the character relationship charts (the printed one blows the secret of Matthew's ancestry; a version that only leaked to the internet blows the plot-relevant secret of Amiti's), the game itself has an in-game encyclopedia, which is filled with new information whenever words in red text show up. The encyclopedia entries provide a lot of information the NPC chatter and cutscenes do not, and without them, you're going to have a hard time making any sense of the plot, and likely miss several key points and quite a bit of foreshadowing and world-building.
Syndicate (2012) has a lot of background conversations and collectibles that add details.
Several details about characters in the Rune Factory games only come up in an interview, such as Ivan and Raguna's specific relation to the royal family, the fact that Iris is not human-though her actual species is not given, the Sharron can see the future-and also probably isn't human, or that all four dragons look the same as infants.
Marvel Avengers Alliance has Marvel XP, a database which often gives extra details about the plot in its News section and Dossiers.
The X-Universe has a history that goes back almost five billion years (Kardashev Type IVPrecursors are involved), of which the games through X3: Albion Prelude cover about forty. Various dribs and drabs of conflicting information on this backstory have come out of Egosoft over the years, which they finally decided to codify into an X-Encyclopedia packaged with the X-Superbox series collection. In addition to explaining the history and fleshing out much of the setting, it loves to talk about things that aren't even hinted at in the games, such as an independent human government called the Hatikvah Free League, and a race of Sapient Cetaceans on a hidden Boron planet.
Doki Doki Panic had the Big Bad, Wart, already defeated when he tried to take over Subcon according to the manual. The manual also stated that the family's children fought over reading the book and they accidentally tore off the book's ending page, causing Wart's defeat to never happen and allows him to reach out and snatch the kids (the missing page also explains why World 7 has 2 levels and not 3). However, the game itself only shows the kids reading the book before Wart snatches them.
Runescape: A lot of the lore is buried in the website itself and the in game books. One example is the "Moonclan Manual". Most players believe magic comes from the runes the game is named for. But the Moonclan Manual states that they are more of a focusing tool to bring the energy inside the caster out, and it's possible (not in gameplay) to use magic without them.
General Chaos came with a 16-page comic book explaining the origins of the conflict between Chaos and Havoc and giving each member of The Squad a humorous personality.
The Sacred Armour of Antiriad had a comic book prologue showing the Earth being devastated by nuclear war in the future, the ensuing post-apocalyptic civilization being menaced by an Alien Invasion, and the development of the titular armor.
The first two Crash Bandicoot games had this affliction. If you wanted to know things like Brio's relationship with Cortex, what makes Coco so special and how N. Gin got the missile stuck in his head, you had to read the manual. Various basic gameplay mechanics were also never talked about, which wasn't so much of a problem in the original due to Crash only being able to run, jump and spin, but new moves in Crash Bandicoot 2: Cortex Strikes Back such as sliding, High jumping and body slamming are never even mentioned. This got better in the third game where it explains how to pull off new unlocked moves, and better still in Crash Team Racing where Aku Aku or Uka Uka would have many pop-up tutorials to explain how to do things.
The plot of the PC game Jazz Jackrabbit 2. The villain from JJ1 has stolen the diamond from Jazz's fiancee's engagement ring. You have to get it back before he uses it to power his time machine and erase rabbits from history. Didn't read the comic in the manual? Then you wouldn't know any of this.
The wiki article of Super Charisma Bros clears up a lot of things that are never explained in-game - the events of Charisma 4 were actually a nightmare that Dudim had traveling through a time vortex, and that Dudim was sent back in time after the battle with Brynn due to "excess levels of Bazingonium."
Team Fortress 2 is probably the absolute best example of this. In game story? "You are one color team, kill the other color team". In various online comics and supplementary material? You see a grand tale of intrigue featuring two brothers who founded the aforementioned teams, an Australian man that's Testosterone Poisoning incarnate, a woman in purple controlling both sides and the long lost third brother and his army of robots, all revolving around a plan by the deceased father of the two brothers meant to punish them for their idiocy.
Assassin's Creed goes a bit overboard with this. There are numerous tie-in books and comics that explain backstories of major characters which are only ever hinted at in the games, particularly with Daniel Cross, whose appearance in Assassin's Creed III will be completely confusing unless you've read Assassin's Creed: The Fall and The Chain.
Thankfully, Assassin's Creed: Initiates contains most of the information from the books and comics, while providing even further details on the modern day Assassin-Templar conflict with regular surveillance updates.
Star Trek Online has an in-game manual, "The Road to 2409", which tells the story of how the Khitomer Accords were dissolved and the Federation and Klingons were at each others throats again. Star Trek Magazine, however, ends up showing information after that, such as the fate of Captain Data and the Enterprise-E ("Road" mentions that they disappeared while investigating something, Magazine reveals that they returned safe and sound, the E decommissioned and Data retiring to be a teacher) and the adventures of the newest ship to be christened Enterprise.
The main website has two pieces of Sunrider lore, found here and here. More are expected to come up as the game progresses in development.