In Red vs. Blue, Church keeps traveling back in time in order to set something right, failing and having another whack at it. At one point he meets dozens of versions of himself who each tried different things to get history back on track. One of them has yellow armor instead of blue, and when the latest version of Church asks him about it, he tells him he's better off not knowing.
MaxterBexter: "Max had a bad encounter with a mojito".
Destin told us Adam was banished from the site over the noodle incident, probably as a shout out.
Due to the strangeness of their work, many Protectors of the Plot Continuum agents end up with at least one; for example, in the Original Series, Jay and Acacia fed a Sue to the Balrog. They weren't quite sure how a creature apparently made entirely of fire eats, and wanted to see. "Osmotic incineration? Perhaps it devours them alive and they flake away inside it?"
Jay's camera flashed away as it [Classified! PPC protected information.]
The SCP Foundation has quite a few, most notably when [DATA EXPUNGED].
SCP-447 is perfectly safe... just as long as you never let it near any dead bodies.
Dave: Oh man. Like that time we went to the Arbuckle Residence and in the basement found those three dead—-
Mike: Shut up Dave! OK next topic...
Unanswered questions abound in The Saga Of Tuck, but given the author's tendency to withhold information until the last second, these are probably the safest to mention:
Just what did Travis do as a favor for Lisa?
What happened during Mike and Tuck's last dual babysitting job?
Why were panties found under Brian's desk?
Where did the missing air compressor go?
In Void Dogs, Galatea was bounced from the casino station for doing something that took more than seventeen pages for the station security to describe, as that's how much of the report was redacted from it.
There's a particular incident that's been mentioned several times. At the end of spring and fall terms, the students in the Super Hero School Whateley Academy have to participate in what is called the Combat Finals. In Chaka's first term at school, when everyone else was fighting one-on-one battles, the instructors pitted her against THREE opponents (a super-strong brick, a giant, and a badguy wizard/manifester), and threw in a series of massive disasters including (apparently) an earthquake and a tornado. All that the readers know is that she totally kicked ass. But people keep bringing it up; it's been officially verified by one of the Canon Cabal that it will NEVER be seen in detail. (Forum, Questions and Answers, Fey's combat final.)
They have a literal Noodle Incident as well. All they've told us about it is that those were not really noodles, and Generator was behind it.
Oh, and don't forget Belphegor's Disco Ball of Doom. And much of Belphoebe's shopping trip is not actually described, we only hear the dialogue.
A DRAMATIC example is used in Against Ill Chances, where suddenly the main character's personality changes subtly, and he can't remember what happened on the second day of testing, and one of his friends is missing... Later we found out. It's a lot worse than you'd guess.
Three new noodle incidents appeared recently: Team Kimba faced an Unwinnable Training Simulation and got their asses handed to them the first time that term (the Grunts, the supposedly the best team in the Sims, needed three or four tries). Generator proposes a strategy that includes a Radioactive Condor Girl and scares the crap out of battle-hardened combat teachers. After the weekend, they (apparently) try this scenario thrice more, ending with the Radioactive Condor Girl strategy. And win. We don't have any details, however.
You're bound to get at least one of these if a webcomic gives one of it's characters a Twitter account, if only because of the limited space available to tell a story. For example, Max Facepuncher from The Fancy Adventures of Jack Cannon. His escapades so far as revealed in the comic, and his own Twitter, show that although his name is a clear indicator of his purpose, it's probably only scratching the surface of what he did to piss off Goofy enough that he got banned from Disneyland.
In the 3rd RP of Darwin's Soldiers, Alfred mentions that he can easily tip over a 3 ton pickup truck. How he knows that is never mentioned.
Sgt.LarryMasters is nicknamed Sgt. Pepper. It is not explained how he got that nickname aside from the fact it involved some Tabasco sauce, his uniform and some beer.
Doomsday Arcade: Maybe more of a lampshade character: Mario refers to 'The Man Upstairs' he is actually working for throughout the entire series, without giving anything else away. Then at the series finale, Lund completely shatters the wall and explains to several members of the audience that no matter who 'The Man Upstairs' turned out to be, it would be a disappointment. So HE NEVER TELLS US.
In this original fictionpress story a Ouija Board incident is mentioned in chapter 23 of the story. Over 100 chapters later and still no explanation.
Here's another one. I'd really like to know the story as to why that person was in Tehachapi and what happened while they were there.
Todd in the Shadows mentioned one in his review of "Like a G6" : "I'm not having any bottle broken over anyone's head in this room, not after the DL incident. I'll tell you about it some time... So much blood !" (he explained it on his Twitter and his "Grenade" review)
The Lupa Fiasco from his Top 11 Songs of 2011 list, which apparently involved several geese, something painted on the ceiling, and a freshly-boiled haggis.
The Motley Two has the mysterious incident which ended up with one of the protagonists getting a robotic eye, and the other a robotic arm and leg. No word on what it was, but it happened on Homestuck's Alternia, and violent incidents like these are hardly a rare occurrence on that planet.
Vork in The Guild doesn't think of himself as a bad man... well, there was that night he spent at a Hitler Youth Camp by accident...
When The Nostalgia Critic is taken to the future to review The Room by his future self, he discovers that somehow, Sea Horses have taken over the world. The only explaination we're ever given is Future Nostalgia Critic telling him that they really should've seen it coming. The Sea Horses have also outlawed watching The Room and fly now. Neither of these facts is given any explaination.
In the review of The Thief And The CobblerVincent Pricecalls the Critic. He then starts a poem to explain why he rhymes in the movie, then forgets it. The Critic mocks him by pointing out the irony that it's been years after he's dead and he can't remember anything. The only explanation Price gives is that it had something to do with Rock Hudson and a banana cream pie.
This is also done in the Nick Coms episode. To quote: "Granted, I didn't grow up as a girl. At least, not for long. *beat* I have a history."
Correct me if I'm wrong, but isn't this more of a callback to when Tristan's voice died?
As a meme that started on certain Image Boards, we have the infamous I accidentally..., where one posts a sentence beginning with the words "I accidentally...", with the verb removed, frequently followed by the question, "Is this bad?". In many cases one can easily guess which verb is meant (often "wrecked" or "destroyed"), e.g. "I accidentally my save file". In other cases it's pretty much a mystery, thus qualifying for this trope: "I accidentally 93MB of .rar files; what should I do… is this dangerous?"
Has this in the form of 'Yellow Church' whose idea to stop a bomb going off was apparently so bad that he somehow managed to change his armor colour from blue to yellow, he even got a special bonus on the DVD where he starts to explain then says 'Ugh, just...never mind'. Inverted in the original series finale where after much begging by the fans, the origin of Yellow Church was finally explained and it turns out that he actually had nothing to do with the bomb and was refering to a different incident.
To quote Tucker: "And I said: Read it? I already ruined it!". Nothing more to that story is given except for Tex thinking that it was disgusting and Caboose not getting it.
Although technically a mythology gag, Both Red and Blue allude to an event at the Lake Hylia Water Temple that made going through it more difficult in Episode 3 of 4SwordsMisadventures.
From Dirty the Pooh Chapter 1: "For Owl, a testicle case, in case he lost his testicles, because... oh well, it would take too long to explain."
Shadow Unit: Sol Todd is a bottomless fount of them, some of which (due to his days as a gonzo journalist) may even refer to real events. (One day, the world will finally hear the Argentinean racehorse story...)
Certain sites catering to*ahem* niche demographics will occasionally have an image up that can make viewers wonder just what's going on in the picture and what lead to the... eh... circumstances, as they are. Assuming they stop and think about what's happening, of course.
In Dragon Ball Z Abridged, Freeza and Vegeta have both mentioned (in their thoughts) a "jockstrap incident", and all that we've learned is that at some point Freeza ordered Ginyu to bury something.
58. The following words and phrases may not be used in a cadence- Budding sexuality, necrophilia, I hate everyone in this formation and wish they were dead, sexual lubrication, black earth mother, all Marines are latent homosexuals, Tantric yoga, Gotterdammerung, Korean hooker, Eskimo Nell, we've all got jackboots now, slut puppy, or any references to squid.*
(Perhaps because it's a nickname for sailors, often used in a derogatory manner.)
Apparently, the last time Mrs. Snob trusted a guy in a hockey mask, she ended up with a miniature Zamboni shoved up her ass.