Deus Ex: Human Revolution: Two Belltower soldiers can be heard talking about the Red Dust Operation. The Texas Secession is mentioned in the Sarif Lobby, which was a Noodle Incident, until Word of God explained it here.
Return To Zork had various characters making reference to a "boar in the forest" joke, which was always interrupted at inconvenient times. One could make the argument that the blacksmith's interruption, "Did you hear the one about the boar in the forest? Ooops, greasy fingers" was the whole joke, as it did gain laughs from the audience when you told it at Chuckles Comedy Club. Eventually the player encounters a statue of a boar in The Forest of the Spirits which must be struck by a sword to uncover one of the missing pieces of the Disc of Frobozz.
In Uncharted 2 Sully tells Nate that they should follow a hose that leads to a campsite, in which Nate remarks, "You always follow the hose. Remember back in Montreal?" Sully answers, "You'll never let that go, will you?" with no explanation as to what happened in Montreal.
Sully has a few of these.
Sully: I'm sweating like a hooker in church. Nate: ...You brought a hooker to church? Sully: Why not?
Much of Nate's past exploits with Sully and a few other characters are briefly mentioned as Noodle Incidents through banter during the levels. In addition to the one above, memorable ones include getting lost in Peru and winding up in jail within a year of Nate meeting Sully, and winding up behind the Taj Mahal naked while taking a shortcut with Dante. For those who didn't play the original game, the references relating to bailing out of Sully's plane and worrying about the parachutes also turn into this.
F-Zero has a "great accident" that is mentioned in every other character profile in GX.
The comic that was featured on the F-Zero X website (and came with certain editions of the game) mentions another great accident in F-Zero's precursor, F-MAX, that killed a great number of people, including The Skull (he got better) and a royal scion racing in it and caused the sport to get shut down.
Half-Life 2 has a "cat incident", involving two teleporters, Dr. Kleiner, Barney Calhoun and a cat.
Barney: You mean [the teleporter]'s working? For real this time? Because I still have nightmares about that cat. Alyx: What cat? Dr. Kleiner: Now, now, there is nothing to be worried about, we have made major strides since then. ...Major strides. Alyx: (louder) What cat? (later as Alyx is stepping into the teleporter.) Dr. Kleiner: (checking the readings) Conditions could hardly be more ideal. Barney: That's what you said the last time. Alyx: (in the teleporter) Hey uh, yeah, about that cat... (One in-game week later.) Barney: Did you hear a cat just now? ...That damn thing haunts me.
However, the "microwave" incident mentioned by Dr. Magnusson in Episode Two is a Brick Joke; it's something that you can do in the original Half-Life. For the curious, before the plot starts in earnest, you can fiddle with a microwave until the casserole inside it (and the microwave itself) catches fire and explodes.
There is a Steam achievement in Half-Life 2 that you can get for breaking a small test-teleporter during that scene. It's titled...you guessed it: "What Cat?"
Metal Wolf Chaos gives us a Noodle War in the form of the Arizona Conflict/Insurrection that Michael, Richard and several others are veterans of.
In the Castlevania mythos, the titular castle was sealed within an eclipse, and its master was Killed Off for Real, in a climactic battle in 1999. However, that's all we know of the event — it is only ever referenced in the Aria and Dawn of Sorrow games set after that battle, where the reappearance of Castlevania is cause for much concern. As of this writing, IGA has expressed reluctance to tackle the issue, as fan expectations about exactly what happened in 1999 have only increased over the years.
Portrait of Ruin also mentions the battle of 1999, despite taking place before it. At one point the characters mention a prophecy that Dracula will be finally defeated for good in a battle in 1999. This prophecy is cited as the reason why PoR's main character Johnathan Morris has the Vampire Killer whip, which is usually used only by members of the Belmont family. In order for the prophecy to come to pass no Belmont is allowed to touch the whip until 1999.
Sam & Max, in the Telltale episodes, constantly refer to events that happen in other cases without getting into the specifics. Examples:
Max: Great, now what am I going to do with the buckets of sea monster blood?
Sam: Remember our old car, Max? Max: I said I was sorry!
Sam: (looking at a dartboard with one dart in it) Someday we're going to finish that game. Max: I'm still trying to get the rest of the darts out of the police impound.
This is also present in the first game, Sam & Max Hit The Road. Early in the game you can...not go upstairs. When you try...
Sam: We don't go upstairs. Max: Not since the accident.
These blend impressively seamlessly with references to older games; for someone who hadn't played the earlier games, things like the man locked inside their closet and Max's election to the presidency seem nearly as noodley.
And then there's the intense, bizarre phobia of porcelain.
Tales of Monkey Island starts at the end of an adventure we don't get to see. Apparently, it involved LeChuck being reincarnated as a walrus.
The Secret of Monkey Island includes a long scene where Guybrush tries to get the Idol of Many Hands from the governor's mansion, almost all of which takes place outside of camera range, though the action prompts still pop up. They say things like "Hypnotize Infuriated Rhino," and "Push tremendous Yak."
Metroid Prime 3: Corruption had the Horus Rebellion that was mentioned by two Federation members. Nothing else was mentioned about it besides the fact that it was apparently as bad as the events of the game.
The opening video shows bits of Kanji's beatdown of the bikers.
As for Persona 3, we never find out exactly what Mitsuru's "executions" entail, but it's become a bit of a Running Gag, to the point where her title in Persona 4 Arena is "The Imperious Queen of Executions". (Fanon tends to depict it as something...kinky in nature.)
In Mass Effect 2 there are various including missions Jacob and Miranda went on (which are explained in the IOS game).
Jack's list of entertaining crimes including dropping a starbase on a moon and hijacking a military craft. While she explains the starbase, sort of, the incident with the military ship is never explained other than "Shouldn't have left the thing unlocked. Besides, parades are boring. I helped."
Then there's Mordin mentioning how he's killed people with guns, knives, drugs, tech attacks, "once with farming equipment," but never with medicine! Mind you, in the DLC, you find out just what the farming equipment was. He killed a krogan by stabbing him in the face with a pitchfork.
A rather suspect one can be found by talking to Liara during the approach to Saren's base on Virmire:
Dr Liara T'Soni: I don't know which is worse. The geth, or all this sand in my...never mind.
A minor one from the Lair of the Shadow Broker DLC: Thane's dossier mentions that he was responsible for an event on Omega called the "One-Hour Massacre".
The setting has an entire Noodle War in its background with the Morning War between the quarians and the geth. Exactly what happened during the war is unclear, and we only get a vague understanding of how it was fought. All we really know is that the quarians panicked when the get began developing sentience and tried to destroy the entire synthetic race before it could rebel and destroy them, and the geth fought back. Many quarians tried to protect the geth and died during the war, and the conflict ended with only about sixteen million surviving quarians who the geth deliberately allowed to escape because they didn't judge themselves able to accurately judge the consequences of causing the extinction of another species. (By comparison, two other major wars in the setting's background, the Rachni wars and the Krogan Rebellions, are more extensively covered by the setting's lore). This makes sense: the Morning War only involved the quarians and the geth, and the quarians don't like to talk about it (as for the geth, well, they kill anyone entering their territory). Naturally the rest of the galaxy does not have detailed information on it.
In Mass Effect 3, it was explained that the war was not because the geth were attaining sentience, but because one quarian freaked out when one geth asked "Does this unit have a soul?" This was not the first time such a question had been asked, but it was the first time that a quarian had freaked out because of it
Kaidan mentions in Citadel that he once had an encounter with the vorcha mafia at one of their casinos. His only elaboration is that he got 5000 credits and a bottle of whiskey out of it.
Then there was the time Garrus killed two mercs with one bullet. Rumor had it it was actually three mercs, but what actually happened was, "The third guy had a heart attack. Not fair to count him."
Matriarch Aethyta uses a noodle incident to impress on Shepard why s/he shouldn't eat anything dextro-based.
In BioWare's Dragon Age: Origins, some of your party members will reference various noodle incidents — such as Zevran's mention of the stages of lanthrax poisoning ("I watched a man go through all seven once!"), Alistair's childhood ("I locked myself in a cage once, when I was a child, for an entire day. Ahh, good times..."), and the time Leliana rode on the vanes of a windmill.
Isabela is behind a few noodle incidents, such as a bar fight that turned into a twenty person brawl in the streets and a letter apologizing to Hawke because she "expected treasure, not spiders". Hawke can mention the last time she was certain she'd found the Relic, leading them to spend most of the day searching the Wounded Coast, only to find a chest containing "several badly written poems... and an old boot". In Legacy, she misunderstands Fenris' attempt to ask her about the time she freed some slaves and informed him that she didn't ask for the goat, and the fire was accidental.
Party banter between Isabela and Anders implies a possible Forgotten First Meeting and drunken liaison, as both frequented the Pearl back in Ferelden during the Blight and Isabela vaguely remembers hooking up with an apostate at one point. Then she starts fondly reminiscing about Anders' "electricity thing", prompting Hawke or Varric to cut that conversation short.
Most of Hawke's first year in Kirkwall becomes this, due to Varric not actually meeting them until Act I. We never find out the circumstances of how Hawke met and became friends with Lady Elegant, Tomwise and Worthy.
Why did Varric name his crossbow Bianca? "There was a girl, and I made a promise." It's the one story he can never tell. (On the other hand, it may be coming up in the comics continuity...) It still applies in-universe:
Merrill: You can't say that! Now I want to know even more!
A Female Hawke can open a letter meant for Carver, where a girl named Peaches alludes to an illicit rendezvous they had in her father's barn back in Lothering. Isabela also mentions seeing Carver "and his chin" regularly in the Blooming Rose, chatting up one of the prostitutes he has a crush on.
If Merrill is romanced, it's mentioned that she apparently swings on the chandeliers in the Estate, destroys cupboards whilst climbing on them (both usually with Sandal as her partner in crime) and Hawke has to routinely apologise to their various neighbours when Merrill wanders into their gardens with no shoes on, starts picking flowers, before cooing at their attack dogs.
Medic: ...It gets better! Vhen ze patient woke up, his skeleton was missing, and ze doctor was never heard from again! *laughs* Anyway, zat's how I lost my medical license.
BLU Spy's severed but still living head is also being kept in the Medic's refrigerator for some reasonnote a later released animated storyboard reveals that the Spy was decapitated during an attempt to infiltrate the base and then rendered immortal by a prototype Medigun.
Spy: Kill me.
In the 2011 Smissmas comic, the BLU Soldier acts the Scout's court-appointed lawyer. When Miss Pauling asks the BLU Spy how that happened:
Finally, we have issue of the Pyro's gender, which Valve is keen to tease about. Their official stance: it's one of those questions "that get asked so often that they become, in a sense, unanswerable."
Disgaea: At some point, Laharl is blackmailed with an "embarrassing photo", but we're never shown what it is. Laharl, Etna, and Flonne have some interesting reactions to it, though.
In Dwarf Fortress, dwarven crafts, engravings, and statuary frequently represent events from the world's randomly-generated history. Unless you have a spare copy of that world to look at in Legends Mode, you'll end up with a bunch of images of some random creature you've never heard of doing something irrelevant.
General consensus among the fans is, if your Dwarf Fortress experience doesn't leave you with at least one story like this, you haven't been playing long enough.
Reddit user: I had a game where a kitten killed a cyclops, but beyond that my experience mirrors yours.
In the Red Leaf High event of MapleStory, AthenaPierce will occasionally say "...And that was the time I ate an entire donkey."
In Left 4 Dead 2, Ellis tries to regale his new friends with stories about his buddy, Keith, who apparently has a tremendous misfortune and frequently becomes involved in fantastical acts of self-endangering stupidity. However, Ellis is most often interrupted with "Is now really the time?", so we don't get to hear how Keith survives. If Ellis' tall stories are to be believed, Keith...
Suffered from third-degree burns to the majority of his body (on two seperate occasions; making fireworks and deepfrying a turkey).
Was teargassed by the police (the effects of the gas blinding him for a whole year).
Snuck a paintball gun on a rollercoaster to invent a new sport. Also falling off the coaster and having to dodge carts because the carny wouldn't stop the ride.
Was buried alive after falling down an open manhole.
Was nerve-gassed and cluster-bombed by the US Military.
Ran himself over with a riding lawnmower he fashioned into a bumpercar.
Received an "I'm a Moron" tattoo on his forehead for a $200 dare.
Ate three pounds of raw chicken (the resulting salmonella paralysed his right foot and obliterated all memory of his brother, Paul).
Tried to stage a recreation of Colonial war in his garden, but only ended up with a raccoon fight.
Lived in a graveyard for a year after he was kicked out of home. He was stabbed and robbed by a man wearing a bedsheet, pretending to be a ghost.
Nearly drowned in a Tunnel of Love..
Broke both of his legs after plunging his car over a cliff.
Joined a couple in Matrimony despite not being a minister. (He would have been married himself, had he not have run away from his own wedding.)
And according to Wordof God, Keith is not imaginary. To be specific, the producer said that Keith is an imaginary character, "but this is a video game, so aren't they all?"
In one of Guild Wars 2's opening Asuran quests (the Synergetics questline), your character refers often to a "sewer incident" involving his krewe's invention, a teleportation device.
In The Silver Lining, Hassan explains that he was almost executed and can no longer enter the Isle of Wonder. When Graham asks what he did:
Hassan: Er... well, let's just say I had two gold earrings, Sire, and I'm not likely to get the second one back any time soon.
Fallout: New Vegas had Incident Playtime with cyberdogs involved which took a sizable chunk out of the budget of the Big Empty. Given the fact the female cyberdog was in heat, lets just say that it was mating season and a lot of sterilization (of both the cyberdogs and the resulting mess) was involved...
With no established personal history, most of the Courier's backstory is this. Various dialogue can mention various places they may have visited such as New Reno and male Courier's with the Lady Killer perk can imply they fathered a child in Montana, but these are entirely optional.
Jak II: Renegade: Who knows what happened with the wumpbee nest on Jak's ninth birthday?
In Chrono Cross, the rise of Porre as a military superpower and the fall of the Guardian kingdom came across as this to many players, especially since Crono, Marle, and Lucca returned home after beating Lavos in the first game. Even the DS Updated Re-release of Chrono Trigger, which reveals Dalton as having masterminded the fall of the Guardia, sheds only a little bit more light.
At the end of Super Mario Galaxy 2, Lubba actually tells Mario that he met Rosalina before. However, it's never explained when the two last met, and Lubba isn't even in the first Super Mario Galaxy game at all.
And speaking of the first Galaxy game, in the prologue, just right before she is captured by Bowser and is carried off into space, Peach can be seen with a little white Luma in her hands (who will then help Mario save her from Bowser). However, it's never explained how, where, or when she got that Luma in the first place.
The "Baconslicer Incident" from Fantasy Quest leaves even grizzled ogres trembling.
Skyrim never tells you outright, but it looks very much like you were a victim of mistaken identity on the part of the Imperial Legion. It seems they were rounding up Stormcloaks at Skyrim's border and you were in the wrong place at the wrong time. Now the Noodle Incident becomes why you were crossing the border into Skyrim.note If you play as a Dark Elf, it is assumed by your captors that you are a refugee. If you are a Nord, you're assumed to be simply returning home.
Arena does indicate why you are in prison: you were a member of the Imperial court in the way of Jagar Tharn's plans. This still leaves open what crime he put you in prison for, and whether he framed you or took advantage of something you'd done.
Beirut in Call of Duty 4: Modern Warfare. This may have to do with Soviet special forces operation in Beirut in October 1985, but all the player as Soap hears about it is:
Kamarov: Hm... I guess I owe you one. Gaz: Bloody right you do.
Planescape: Torment has one in the form of party banter. Various party members will ask Morte, a floating skull, what happened to his body, but he refuses to answer beyond "It's a long story and it involves the Head of Vecna." note He's lying; you learn later that his soul was condemned to the Pillar of Skulls when he died for telling a lie that resulted in someone else's death. The real Noodle Incident is the circumstances under which that occurred; they may or may not have involved you. Morte himself doesn't know.
There's also whatever your first incarnation did that got you into the huge mess that is the Nameless One's plight. The only thing we know is that it was unimaginably horrible, enough that the Practical Incarnation, who might we remind you faked loving a woman so she'd stick around as a ghost after death, doesn't even come close.
In the MMO Rift, during one of the Storm Legion dungeons a boss states he hasn't "Had this much fun since the Blood Tornado Incident"
(Enter and Return are picking up a stretcher with a choking victim on it.)
Enter: Well, don't drop him. Return: You mean like that other guy? Enter: Whatever happened to him? Return: Who? Enter: The other guy. Return: We dropped him! Enter: Well, don't drop him!
Iris Heart racks up quite a few of these, partially as a result of being prone to acts that can't be shown without raising the game's rating. She even has one before her first on-screen appearance: we never find out exactly why Noire wants to stop Plutia transforming at all costs, just enough hints it's almost surprising when Iris Heart suggests Noire has virginity left to lose.
Another early one (and her first appearance, natch) has her arrive to bail her friends out after a Hopeless Boss Fight, carrying two Plot Coupons and dragging the unconscious mouse/rat/Pikachu-knockoff thing that had them behind her. The villain tells her not to be so proud she beat the items out of a rat, to which Iris Heart replies she didn't just take them, they were payment for services rendered. It isn't revealed what happened between her transformation and arrival, but from what wefind outabout her, the implications are... unsettling.
When the Blacker Baron first appears in Anarchy Reigns, Jack notices he's wearing a pair of flaming gloves, which he notes were taken from a "pyromaniac sex freak" they hunted down. "You... do know where those have been, right?"
Eggman's explanation in Sonic Generations involving his defeat in Sonic Colors definitely comes off as this to those who had not played Colors, especially because far more people have played Generations than they have Colors.
In Sonic Lost World, Tails mentions having once built a television set out of paperclips and having reprogrammed a supercomputer with nothing but dishwashing detergent and a toothpick.
In Pokémon Mystery Dungeon: Gates to Infinity, the seemingly mellow and laid-back Quagsire gives Scraggy some manner of punishment for his crimes that was terrible enough in the latter's eyes to make him obey his directions without question, on top of panicking if the former so much as emits a 'Hmm?" in his direction. He goes on to note that he was once famous in the underworld, and Virizion also makes mention of him being quite the character back in his glory days, though specifics are never brought up.
Rune Factory 3: No one will explain to Micah what happened the last time Blaise drank wine. Whatever it was, it was public, it was embarrassing and Blaise swore off wine because of it.
Video Game/Skylanders: Giants has a scene in which Captain Flynn needs some supplies and sends you to get them because "Unfortunately, due to a 'misunderstanding', I'm not allowed to set foot on this island. Heh, it's a long story." Later, after you have taken down an entire tribe of evil, elvish beings called Drow and taken a magical compass that they have been worshipping.
Flynn: Wow, that went way better than when I tried it. Cali: Wait, you tried getting this before? Flynn: Hey, I said it was a long story!
In Saints Row IV, there's whatever reason Kinzie had for rescuing Keith David first. All she says is that he "was on the way" and cuts Keith off when he tries to explain. Keith just responds "Oh. Ohhhhhhh" and drops the subject.
A homie conversation between Shaundi and Fun Shaundi will have them recall "that time at the North Pier with Randall and Jackie". It involved fireworks and fuzzy handcuffs, apparently.
Danganronpa never explains who won the sauna endurance match between Ishimaru and Oowada. But whatever happened, they went from bitter enemies to Blood Brothers afterwards.
Peter: No names, Ray. I don't want to get too attached to this kid. Remember what happened to the last one?
Along with other lines, the implication is that the last test subject, I mean rookie, was testing something potentially dangerous and ended up in New Jersey. Possibly by explosion.
GoldenEye007 has one mission where (on the higher difficulties) Bond has to plant explosives in a missle silo and get out before the automatic timer reaches zero. On of the pre-mission briefing files talks about having to work quickly once the first set of explosives is planted - that particular memo ends with "remember what happened to 004 in Beirut."
Out of the 100+ heroes that are in Dota 2, hardly a single one has a bio that isn't chock full of them.