Aborted Arc: Some arcs fail to finish, leaving things hanging.
Etheru's "New Homunculi Arc" will probably never start, due to the fact that the player himself has no clue what to do with the idea. Same with the Grimmoire Arc, and several other ideas, though he does play with the idea of going to the locations, sometimes.
Hydronix's Quest 64 Arc. It unfortunately happened offscreen instead, due to some lack of interest in playing it by some tropers.
Bass can use the Guts Upper, and he often talks about Link while referring to the voice, all three characters were voiced by Nobuyuki Hiyama at some point.
Catgirl!Osaka's verbal tic makes her pronounce "everyone" as "everynyan", a la Chiyo's dad.
Adaptation Distillation - This trope is sometimes applied by simplifying events and complex characters from the source material.
Alternate Universe - A major element of the story, and the excuse for why there's multiple versions of so many different characters running around.
All There in the Manual - Sometimes happens for the characters, especially original characters.
And Now for Someone Completely Different - There was an entire arc based around this trope, where the old cast was temporarily left behind and everyone played new characters. These characters have since been assimilated into the main group, though, and there was the second one which started on the first anniversary of the game.
Another one of these arcs was more of an Alternate Reality Episode: each player played alternate versions of their more established characters and had them interact as if they were only recently introduced to each other.
Anti-Magic - Juergen has a condition that has a magic and psychic powers dampening field around his immediate vicinity, it also unnerves psychics around him, and even harms them when they get too close to him.
Anthropomorphic Personification: Sort of done with the "Concepts", which are moreover concepts like emotion and ideals given form.
The first happened on 4/1/2011, where several players took advantage of the changing avatars by playing them as gags.
On 4/1/2012, many characters showed up in place of the group as one-off gags. Most of them were from the twospinoff roleplays, the other characters were Others. In addition, several characters played pranks (Catherine Grayson cosplayed as Vriska, Vivian prepared some Explosive Runes, Envy and Nue played tricks on Maggie and Hilarity, etc.).
Ascended Extra: Harry, Faker!Metis/"Raven", Chaos Deviot (present version, though this is arguable), Bassy, Scorpion (may be the only true exception to this trope here), Kokonoe and her crew, WarMECH, and Future!Joey Jones.
Etheru used a few characters who only got a few moments of characterization (Emily, Obelisk, Ami, and Marjorine) in the The Bus Came Back arc.
In between the Writer and Tale of Two Yukaris arcs, Catherine's other Lightspeed Rangers only showed up to try to help the group stop the Retconinator by shutting down the Morphing Grid. Come Alyx'sOrigins, they actively helped Catherine, her family, and Alyx, to the point of being involved in the final battle.
Author Appeal: People who play the game will often use this.
Lesbians are a common kink shared among some people in the game.
Author Filibuster: Etheru used Bass to violently lash out at the Characters and the Tropers, but afterwards, Etheru tried to make amends with the Tropers, and promised not to do it again.
There was a brief period of time where Osaka would not shut up about Dee. She got better, though... before getting worse again.
Averted in a battle with Xavier's Him, despite looking like it at first glance. Etheru said Mega Man wasn't channeling a dislike of commonly used ideas in the game, Mega Man was just that pissed at having to fight yet another opponent with sadistic kinks and other things encountered before with previous opponents.
Badass Santa: Santa Christ, who randomly appears to help brutally smack down Apos. Afterwards, he briefly solved any problems the Avatars asked him to solve.
Bad Future: The Incarnates Arc takes place in one of these.
Big Eater - Carter, lampshading that he doesn't gain a pound constantly, until...
Balloon Belly - In the world of Pokemon, Carter ate more than four hundred hamburgers, resulting in quite a bloated stomach, and instead of being brief, he had to work it off. And then it happened again with every single Grayson ever since, with the exceptions of Matt, Andreus, and Alyx (and even then, her weight gain is fairly realistic).
A non-Grayson (at the time) example would be Arcadiarika herself in-game, also due to a result of overeating. However, unlike the Graysons, she had a Gaki inside her body, which could explain her sudden and permanent weight gain.
Bittersweet Ending - The Witches Game arc; on the one hand, the trolls can't bother the main characters anymore, but on the other, Featherine can.
Not to mention Victoria Grayson dies. Granted, she got better, but...
This was considered a very controversial decision, especially when there were a million other ways to write out Victoria without killing her. It also did not provide anything to the plot at hand, so even if she was brought back, she died anticlimactically and died for nothing.
Black and White Morality: Players mostly try to avoid this trope, preferring to go for ambiguous morality. Although some characters have this viewpoint.
Blue and Orange Morality: Tabika won't drain anyone she knows or likes, but sees nothing wrong with killing strangers in their sleep. Unless she thinks she's about to get into trouble, of course.
Book Ends - The entire conflict with Kasei/Araragi ends with a Lucario (Gijinka or otherwise) being used as a battery for a machine.
Breaking the Fourth Wall - This was a prominent running gag, where characters like Bass, Deadpool, Bernkastel, Raven, among others, would refer to the readers and the people reading. However, the gag was done to death and it's since been downplayed.
It got to the point where Etheru retconned the ability out of Bass because of annoyance with the gag.
Brick Joke: At one point, Bass told Asagi that she was in a dating sim. A hundred pages later, she still hasn't exactly been told otherwise.
In a more recent adventure, the gang has landed at a refueling station that's nothing more than a truck stop in space. Almost immediately, newcomer Pilot Solaris, his friend Human, and Grey enter a bar. Pilot's first action is to drink a shot of whiskey, and Human orders a coca-cola. Several hours (and several pages) later, Pilot returns to the bar, and Human is gone—and a pile of empty coca-cola cans is sitting next to his now-vacant seat. We don't see Human again until the next day, when he's seen leaving the bar and making a note to never go on a coca-cola binge again.
Capcom Sequel Stagnation- It's mentioned in the discussion that, in most plots involving the Multiverse being conquered/taken over/attempted to be destroyed, there's rarely any variation, the plots feel the same most of the time. Predictably, it's subject to a lot of parody.
Catgirl: Hina (sometimes), Nepeta, Ozzy (sometimes, anyway), later Osaka. Even "Raven" got into it. We also have some catboys, and an entire set of pages where everybody was a cat person for a while.
Ax lampshades this trope when he wonders why there are so many cats, catgirls, or cat-themed characters in the group. The answer? Because Cute Kitten.
Cerebus Syndrome - Somewhere around the first Wham Page (see below). This has been slowly happening since the beginning; it started out as avatars just interacting randomly with each other with no plot whatsoever. By now, there's a highly active discussion thread.
Characterization Marches On - The Trolls from Homestuck got this treatment a lot. As more and more information was revealed, some of the information contradicted some stuff established in the game. Not that it hurt anything, considering that they could easily be handwaved as Others.
Apparently, before Carter/Catherine became known for...that, he originally was a bit parodic, showing PSAS at opportunities, but then...
Chekhov's Gunman - Several homunculi appear at various points earlier in the game before being the center of a story arc.
And Connect Four with Death. And Pokemon Battle with Death. And Poker with Death.
Chronic Hero Syndrome: Mega Man and Jack are hit with this hard. Catherine too, to some extent, but she, at times, refused to help certain people.
For the latter, this was lightly deconstructed when Carter left Jennifer to save Martin, leaving the new girl confused. He then promises to tone down his tendency to save people's lives...which ultimately did happen during the Skyrim arc.
The Cloud Cuckoolander Was Right: Kari points out that, technically, it was Arcie's fault for letting the other Legendaries in the Pokemon world grow up to be so dysfunctional. Arcie agrees.
Cool Big Sis - Osaka, to Dee. Over time, though, their relations got worse with Osaka becoming incredibly obsessive over Dee, which resulted in Dee leaving the group.
Cool Sword: Joshua Strasin's warblade, a valgirai weapon that absorbs UV radiation and then upon activation goes all lightsaber-y.
Caim's Strifesword, which he got from killing the Goddess of Strife.
Crapsaccharine World: The world future Tails lives in is seemingly an amazing place, and Tails has the fortune of being the president of a non-corrupt Mega Corp. However, the corporations that are corrupt are far too numerous, the Earth has been in a war between Oceania and the Furon Empire over who gets to enslave the populace, and Tails' position causes him to be a frequent assasination target, losing an eye and an arm on two seperate attempts.
Creator Breakdown: The 'Great Schism': wherein Gloom Rage Quit, Lemurian threatened to, and Katsuun went off the deep end.*
To elaborate, it happened when the topic of whether or not the group are heroes was brought up. Gloom insisted that they were Designated Heroes, to the point of posting a webcomic strip that firmly sums up his opinions—that they need to die for the good of everyone else. Eventually, angry over them not being heroes in his eyes, he quit the game. Lemurian threatened to quit because he also believed that the group should be heroes. As for Katsuun? This was the trigger to all his resets and using alts for said resets. To sum it all up: it was a bad time during a transitional period where the RP grew the beard.
Later, there was the Midna problem, where the titular Troper was called out for being so obsessive towards Mana, leading up to the in-game ending of Osaka and Hilarity's marriage, everybody snapping at everybody about a plan that was initially proposed to make Midna leave, and finally Midna's banning. Needless to say, no one was happy with the outcome.
For an individual example, arcadiarika is rather... an interesting case. She started off fine, but after approximately the Father arc, she would turn negative. Her characters became affected because of her attitude, and to keep it short and simple, Wangst occurred to the point where, at one point, one player was fed up with her attitude and quit—granted, she admitted that she hated him, but that was not a good excuse.
But then came her "break" starting in December, and while she hasn't officially rejoined the game yet, she seemed to have gotten better, as she acknowledged her mistakes in the past and took great lengths to fix them by using different "What If?" scenarios, ideas for potential arcs/mini-arcs, and new character ideas. She also had greatly mellowed out for the most part and gained a more positive self-esteem overall. Due to her short sessions, it showed that she kept up her streak.
Irene is a bit of a different case. A huge amount of factors led to it, most notably his mediocre (or so he says) roleplaying skills, the game feeling stale, and nearly all the jokes coming from a series he didn't enjoy, leaving the whole RP boring overall. Multiple other factors were apparent, like the lack of really good newbies who actually showed promise (three in total at the time, the rest... not so much). None of these factors have changed, making his at-first temporary leave a more permanent one.
Crapsack World - The World the Consolebots come from. Even after the Great Liberation, it's still pretty bad.
From a world of Superheroes comes Dusk City, a city full of pollution, corruption, and a few other things, including superpowered criminals and an arms-smuggling ring. The Past District in the town, which bases itself in the 30s and 40s, actually seems more pleasant.
The world of BlazBlue was already pretty crappy. However, the Bad Future Hakumen comes from is implied to be even worse, with Terumi as Imperator Librarius in all but name. It got to the point where La Résistance, spear-headed by Kokonoe, began to search for allies from other worlds to replenish their badly depleted ranks— leading to Hakumen meeting the Group.
Crazy Cultural Comparison - Asagi Asagiri has this because she comes from a series where there is No Fourth Wall... which translates to her coming from a home dimension where everybody has an intrinsic understanding/belief they’re part of a video game, and all the terminology/concepts that come with it.
Cute Mute - Game-changing character Bit started out as one of these, then minus made her able to speak, and freed all of her kind.
Tails Doll is only able to be understand by a small list of people, considering he speaks in Mmphs.
Dangerously Genre Savvy - One of GG's superiors was this, having gotten rid of the papers and data on GG's identity before he got there.
Demoted to Extra - Dee, up until very recently. Shortly after 3Dee's introduction, she would usually only say anything whenever Cupid was involved or during introductions and would tend to sleep the rest of the time.
And then Rachel Elizabeth Dare appeared, which pushed Dee's speaking appearances back down into "pretty much nil" territory. You just can't win, can you?
Dee got better, leaving Osaka's Other to fall into this territory; she was a pretty major character in her first appearance very early on, but lost most of her screentime to Dee and 3Dee in her subsequent appearances, due to her writer's preference for the desdroids.
Dee eventually left due to relations in and out of character spiraling out of control, causing Dee to leave.
Protoman appears a lot less, but Etheru is trying to give him more appearances.
Gandalf is usually this. Justified in that he's an old man(despite being undead) that uses powerful magic.
Inverted with Osaka, Lyra, and Lip (less so with the second one) who grew more and more attached to Mana as time went on, to the point it became their only notable character traits.
Dysfunction Junction: Most of the characters played by arcadiarika. Eventually, they got better. By a lot.
Inverted with Drifter, who had a Good Counterpart. They joined the group after the evil counterparts kicked him out for not being evil. After the original Drifter was killed off, he became a regularly occurring character.
There was a previous arc where there were evil versions of the group being led by a Dark Other of Alucard, Adrian Tepes.
Failure Hero: Catherine got a lot of constant flack for this. Arcadiarika said that she made her constantly fail because the group is often accused of being too powerful (of course, those who accused the group never seemed to acknowledge that it is less about the power of the group and more about numbers). As such, Catherine was hit with too one Diabolus ex Machina too many. This was fixed, but at the cost of going the other way by not allowing her to fail.
The Federation: The United Multiversal Federation. Several characters, however, have commented that the Multiverse is too big for one group to police effectively, and that they may have too much power.
Team Pets: Jack Frost and Angelus (although she'll never admit to it)
Arcadiarika's Grayson family can possibly fit the criteria. Though their positions change with the arcs, this is generally how it goes:
The Hero/The Heart/Technical Pacifist: Carter/Catherine, by virtue of being theparent and the fact that his/her leadership skills were demonstrated in both the original canon and, for a brief time, in-game.
The Lancer: Michael. Aside from Carter/Catherine and Matt, he was the most developed Grayson.
The Big Girl: Victoria, even though she's the current holder of the Red Lightspeed Ranger powers.
The Smart Guy (or The Smartass Guy, whichever you prefer): Andreus
The Chick —> Action Girl/Badass Normal: Alyx. However, in Alyx's Origins, she was revealed to be an alternate Carter Grayson, also making her—now a him—The Hero because of that.
Follow the Leader: Several different fora played this game after it was created. One of them is in the Minecraft forums, but it focuses more on adventures than interaction.
Foot Focus: Mana goes around completely barefoot all the time - being 50 49.6 meters tall, there's a pretty good reason why she never wears any shoes. Osaka often sits on and occasionally playfully tickles her feet.
Metal Sonic is angry that he was always left in a lab to constantly be updated while pondering why he was made, and why he didn't have friends like Sonic did.
A less extreme example comes from Red, a fairly cynical character. Her reasoning comes from her world's erratic behavior; it's far from a Crapsack World, but it's given her a cynical attitude.
Izzy's reasoning behind his dislike of Yasmin stemmed from the fact that he was put through painful tests to see if he could replicate her, often being compared to Yasmin in the process. He seems to have gotten over it.
An older Joey Jones shows up as an agent of the Time-SpaceDefense Coalition on several occasions: once while spying on the Group for the TSDC, and once to arrest the Ultimate Warrior (yes, thatUltimate Warrior). He wears Heroman as his Powered Armor. It is implied that his universe was taken over by the Skrugg, and that he was one of the only survivors.
Genki Girl: Windy is a pretty good example. Cyber Amy seems to be a bit different, but applies as well.
Gentle Giant: Mana (almost always, but will fight if provoked), Anne (usually), Ogre (though a fighter), Mammon. In fact, most of these are somewhat subverted. All of them will fight if they have to.
Greek Chorus - The members of Completely Different Inc. are becoming this.
Grey and Gray Morality - Yasmin believes in this trope, though she doesn't like poor reasoning behind people's actions.
Subverted with Modern!Gensokyo, which has been part of the United Multiversal Federation for 50 years.
High School AU: Was a focus of an arc, where Others of the group attended the Jethro Q Walrustitty Boarding School. It was so well-liked that it gained the second spin-off.
History Repeats: When Dee entered the game, Midna promptly became obsessed, and had backlash toward any other characters that Katrika had (such as 3Dee), calling them Wesleys. At some point, Katrika got sick of Midna begging for Dee to be played practically all the time, and she left. She came back briefly, then left due to Midna unsubtly dropping an anvil about wanting to see Dee, leaving a lesson learned. And then Mana appeared, and when Hilarity played Anne, Midna said Anne was a Wesley. While there was no quitting involved, Hilarity still being a long-runner, the events still repeated to the point where Midna was finally forum-banned.
Hope Spot: In Hoenn, Hakurei Miko was about to finally able to go back to her Gensokyo which is a decade overdue. However, Evil Eye Sigma 4 blocked her path and making sure she stay out of her homeland no matter what. Miko was less than amused by this.
Irony: Despite Saturn's distaste for Homestuck (art envy or something), he's created an OC based off the work, as well as sometimes—but not always—trying to involve them in his plots.
Incredibly Lame Pun: Many. Mammon, as well as his player Hydronix, seem particularly fond of these. They range from merely bad to truly cringe-inducing.
Informed Attribute Imca's player feels this way about Imca's fighting skills, since in over a year of being played, she has never once delivered a kill shot, only once managed to be of any actual use in a fight, and tied with Mario in a duel, despite many battles taking place.
Journey to the Center of the Mind : First done with Ozzy, and later with "Raven". The second one was a bit more awkward, since three different aspects of her personality showed up.
Killed Off for Real - Bit, Tails, Matt, all of Team Metal save Iron Amy/Amy Nidorina, Mammon and Guilty, Ime Anne Assman, Future!Chaos Deviot, Future!White Air Knight, and Subject Phi.
Lemony Narrator: Some Tropers have the characters actions in this. Etheru seems to like it in particular.
Les Yay: Nearly all of Cly's characters, non-stop. Others include Catherine, Cyber Amy, Cryshell, and Gabriella. Last one wasn't played with much, in fact, she didn't want people to know it!
Lighter and Softer - After the Incarnates arc, less incredibly dark and edgy arcs became more prominent. Not to say there aren't dark moments, but...it kind of Zigzags, actually.
Loads and Loads of Characters - Lots of tropers change their avatars often, so expect lots of characters to appear, vanish, reappear, and develop in no particular order.'
And by now, nearly every player plays multiple characters at the same time, even if only one of them is in their current avatar, taking this trope Up to Eleven.
Of course, the number of regulars played by each troper tends to vary. Sapphire Flame, for instance, has become quite self-deprecating about the unwieldy number of regulars he plays.
Etheru's gotten a lot of characters, and seems to be following Sapph's footsteps, many of which are Original.
Although Icarael lacks the sheer number of characters Sapph or Lemurian have, he compensates for this by having the most amount of characters with the group (11, counting Kokonoe and her crew plus WarMECH).
Lotus-Eater Machine - The "Ultimate Mercy" that Incarnate!Mega Man uses. It has the strange side effect of keeping people from aging, though.
Lover Tug of War: Sonia, Yuri, and Roll got into this over Bass.
Mama Bear - Osaka is pretty happy and friendly normally, but if you mess with her "little sister" Dee and she's around to see it, she'll tear into you without hesitation.
The usually calm and collected Ozzy will hurt you if you try to harm Mika or Wrath.
Cyber Amy will try to kill anyone who messes with Baby Onix. And she's not hesitant to be violent either.
Hakurei Miko will be merciless to anyone if they try to harm Reimu or even her Others.
Whatever you do, do not attack Catherine Grayson's family or even mentioning the idea of it. She will find the attacker(s) and either talk them out of it or, if they're incapable of being talked out of it, just flat-out attack them.
Mega City: Some characters from Modern!Gensokyo implied their home to be this.
Meta Guy/Genre Savvy - Awe Striker and Ozbourne, due to being humans from worlds very much like ours, often have familiarity with the fictional universes that many of the other characters come from.
Most of Caped Luigis Yoshi's characters also qualify, due to their immunity to the fourth wall.
My Name Is Not Durwood - Osaka often gets the names of things wrong, thanks to her Cloudcuckoolanderness. On page 1815, Lip mistakenly refers to the X-Bot Elise as "Eliza", but hastily corrects herself after a rather harsh response.
Aternian trolls aren't fond of being called "gray-skinned oni", period.
Mythology Gag - Lots, one example comes from Maria Renard's Plasma Whip, which was dubbed, "The Halo".
At one point in the Yellow Devil's first appearance, Sonia commented that the Yellow Devil didn't seem all that powerful. Bass told her to face it alone, and Sonia shot back, telling Bass to face Death alone. There's a particular position those two bosses share among gamers.
Lordgenome talks about Cytomander, Thymilph, Adiane, and Guam in his conversations sometimes, at one point saying that he thinks Thymilph and Adiane like each other. They do.
Tama Saisei is an customized Eyebot with a TV screen for a face. In the Fallout universe, the Eyebots are originally floating televisions◊ until the Enclave redesigned them into surveillance and reconnaissance bots.
Nice Job Breaking It, Hero: Mega Man bargained with Kasei that if they let Luca go, they could look through him. Both sides held up their part of the deal; however, Kasei got the upper hand, as he managed to acquire the schematics of Mega Man's weaponry.
In a similar situation, Aurora struck a deal with Greybaum: if he let Dr. Distatio's robot daughter, Kelly, go, Aurora would give Greybaum directions to a dimension where some Phlebotinum could be found. Unfortunately, by that time, Greybaum had already analyzed Kelly and disassembled her, meaning that the trade came out in his favor.
To make matters worse, Tsubaki was with the group that bargained with Greybaum, allowing Terumi to follow the group via a bug on Tsubaki and offer Greybaum help in exchange for the research data on Kelly.
No Bisexuals: Averted with Gabriella and, for the most part, Catherine. "Raven" as well, oh so much...
Hakumen breaks down when he sees Rota's memories of her rape. To be fair, everyone else broke down at that point too.
Official Couple - Twenty-one. In order of appearance, Joshua/Jeniffer, Bit/Link, Maria/Alucard, 3Dee/Xenos, Dee/Joat, Hilarity/Osaka (now broken up), Michael/Melody, Catherine/Kotohime, Victoria/Lrith, Aurora/Max, Sapph/Anne, Gabriella/Cyber Amy, Lip/Usso, Brian/Garcie (broken up as well, on better terms, though), Rai/Konoe,Ty/Luca (now broken up), Mammon/Lillian (now broken up due to death), GG/Garcie, Falken/Asagi/Imca, Gene/Laverne, and George/Lillian.
In everywhere but the main roleplay, Luca/MegaMan.
Old Shame - Etheru admits that he hates every single incident where Bass broke the fourth wall, even the more tamer moments, because of this, he retconned it away, and hasn't looked back. Eventually developed into a disliking of the fourth wall in general.
For arcadiarika, do not mention Carter's first appearance to her, the one where he came off as a poor man's Deadpool.You will regret it. She also deeply regrets what she did to her characters, which are too many to name. About the only things she doesn't consider as a complete Old Shame were her treatment of Matt, a few moments in arcs (such as the battle between Catherine/Lunara Knight and Protoman in the "Revenge of the Spark" arc and the entire "Curse of the Sea" mini-arc in which Michael does three tasks in order to resurrect Catherine), and the relationships between the Graysons (Michael and Melody, Victoria and Lrith, and Catherine and Kotohime), and that says a lot.
Raidou Kuzunoha and Garcie usually play this role to the Group. Hakumen and Rai have a different approach to things, using the uncanny ability of the Group to attact weird things as snark fodder.
In a group of Evil Counterparts, Nega-Kari, Carona, Evil!Anne, and Leaks fit this role among the psychos, blood knights, and Psychotic Blood Knights. Nega-Kari's a weird example, being the Counterpart of a Ditz who barely knows about social customs.
Psycho!Gamzee, or Sane!Gamzee, whichever name you prefer. It was shocking the first time the stoner went nuts, but now whenever he makes an appearance, it's almost expected for him to flip the fuck out due to lack of Sopor Slime.
Papa Wolf/Knight Templar Big Brother - Mega Man's normally an outgoing, friendly character, but harm Miles, he'll want to harm you to the fullest extent that he can provide.
Deviot is this way about his family. To the point of sacrificing himself to not just save Amy's life, but to kill Incarnate!Yukari.
Pinocchio Syndrome - Happens a few times, most notably to 3Dee but also to Bass and Mega Man, twice.
Now inverted with Sonia, who was happy to try her hand at being a robot.
Sunny wished to be humanoid after the Survivor mini-arc. She is just a cyborg cat girl now, but she does not mind since it is close enough for her.
A little less so recently, but Disgaea might be taking its place.
Rescue Arc - The Impel Down arc, where the group goes to save Link, Franky and Ilyana. Had been delayed for a long, long time.
Luca and Mega Man had to also be rescued from Kasei.
RPG Episode: Once used in a level of Pikadevil's Hell.
Rogues Gallery - Subverted while still being played straight: The group usually defeat/kill their enemies, but sometimes they come back, such as Father and Kasei (albeit briefly).
Running Gag - Mega Man sometimes has a tendency to drone off of something related to the subject, such as an adventure he had.
Jack being mistaken for a boy (not helped by the name and androgynous Avatar).
Hakumen and WarMECH being the last two people left awake at the end of each day.
Random bolts of lightning striking characters and transforming them in amusing ways.
The Silver City hotel's walls being demolished.
And now any Hotel, just to mess with poor Sapph.
When the Fourth Wall is broken nowadays, it's usually accompanied by an aggravated scream by Bass, who's relaxing back in his world, usually growing more and more apathetic to the Fourth Wall breaking.
Screw Yourself: A Think Tank named N30-N suggests that the two Couriers, a male and a female, should make love to each other. No one approved of this at all for obvious reasons.
Self-Deprecation - Some players tend to do this using their characters to point it out, but it's usually considered a bad idea.
To an extent, this has also been corrected; there's still a bit of Serious Business, but at the same time, the Tropers are trying not to take it too seriously.
Shallow Love Interest: Usually averted, although played straight for certain characters.
Ship Tease: Mega Man and Luca's respective players have been having a little too much fun with this recently. According to Word of God(s), though, it's doubtful anything serious will come out of it.
A!Rika/Catherine was teased a bit, though Word Of God says that she only did it for the lulz. She later admitted that she wasn't really trying anymore.
Quite a bit earlier, it was just avoided with Brian and Windy. Though Windy and Were Hare may be another story...
"Raven" and Fred seem to be going this route, whether or not it'll come to fruition is another story.
Roachey and Violet at one point(planned), then later on, Mara and Roachey.
"Raven" and Aya seem to have gone this route recently.
Hakumen and Tsubaki also have their moments.
Mana and Axl, a bit.
Mammon and Lillian. Notably, Lillian was the first PC he met in-game that's not a background story.
This is possibly the case with Wren and Kari.
Adult!Arcadiarika and Wren had their moments as well.
Story Arc - Although the setting is easily changed with some effective roleplaying, some longer arcs have been implemented. After the move to Role-playing, there's always been one or two. Anyone who wants to can usually kick off an arc, and several plots sometimes run at once. Fortunately, this doesn't seem to have become too confusing. Some of the more note-worthy ones are:
Happens a lot in general with arcs, either because a troper is going through real-life issues, or they're too lazy to finish their own ideas.
Shapeshifter Guilt Trip: Apos creates a doppelganger of Bit during his battle with the party.
Shown Their Work: Some Tropers do this to make their characters consistent or accurate, or do it to further the Alternate Character Interpretation. But outside of characters, ideas and concepts are sometimes borrowed by looking through the original plans of some franchises.
Arcadia's done a lot of homework about the Power Rangers/Super Sentai franchises. This is particularly blatant during the "Revenge of the Spark" and "Alyx's Origins" arcs.
Superpowered Evil Side: Dark!Bassy(also known as Feral and Evil!Bassy), Black Frost, argueably any of the Incarnates as is
Super Robot/Real Robot - The Phase Distorter was created from an odd mishmash of both, incorporating technology from several different mecha from different universes. Given the generally soft setting, though, the end result falls into the former category. Its head even looked like a Mister Saturn.
Theme Naming: A very clever one with the Original Character Orange who is named after both a color (to fit in with the Red Ribbon Army Color Theme as he's the brother of Capt. Yellow) and a citrus fruit (as he is the rival of a character from Ranma ½ named Lime)
Melody, the demon that's teaching Roll how to use some demonic power, fits with Mega Man (or Rock) and Roll's music theme, but she's less than a Mega Man character (due to supernatural origin). Interestingly, the name fitting into the whole theme was an accident.
Practically all of the Pokemon Gijinkas.
There Are No Therapists - Averted for the most part; the group does get therapy from each other. Shockingly, though, since Tails left, the group's therapist is Bass.
Terri tried to take on this role towards the Graysons for a while.
Catherine eventually lampshaded by saying that all of her problems and bad decisions would baffle any therapist, hence why it never sticks for her and her family.
Token Evil Teammate - A few players have attempted to create these; they usually fail miserably.
Merchant and Caim may be exceptions to this rule, however. Neither of them really cause a major amount of trouble, regardless of alignment. The problem is that they rarely do anything evil amongst the group, making it hard to see them as Token Evil Teammates.
Bart would be this trope if it weren't for the fact that he's so horribly ineffectual.
White Air Knight and rations. His hawk form prefers bird seed or bread.
Sir Ron Lionheart (and to a lesser extent, Xenos) and DELICIOUS CHATEAU ROMANI!
Yggdra and strawberries.
Ax and cinnamon bun-zah.
Tetsuya Tsurugi and Pork Buns
Snorunt!Yuki and Ice Cubes
Proton and Rolling Rock Beer.
Zora Brian and eggs.
Jack Frost and anything cold, from ice cream to ice cubes.
Jacky and cherries.
Hakurei Miko and cherry blossom tea.
Transparent Closet: Tails was in one for a lengthy period of time, even after having several Erotic Dreams involving Sonic and drawing Sontails Rule 34.
Tsundere : A common character trait, so much so that Taiga once compared it to a virus.
Unfazed Everyman: A common archetype assumed by characters who are unfamiliar with the technology, magic or seetings used in the game, as well as new characters who have just joined the group. Often used as a means to explain to the unfamiliar what is happening in the game. Out of context, newer players also assume such a role when they find their way around the game.
Verbal Tic: As mentioned above, some catgirls use Nya and variations.
"Raven" as a wolfgirl rolls her Rs sometimes.
Jack Frost has his "hee-ho".
Sunny has dood, which she picked up from a prinny with her adaptive speech programing.
The Virus - The Computer Virus, to be exact. In the past, it's infected many of the robotic characters, and most likely counts as Nightmare Fuel.
Visual Pun - Kari's new appearance gave her glasses. She was established as being a little too loyal to Luminosity, making her blind to the truth.
Silver was planned to appear during the Incarnates Arc as a personification of Lust, possibly going to levels of Complete Monster that would almost rival Apos. Daionus decided he did not want to play as that sort of character, and declined.
Also, in the same arc, Catherine was planned to appear as a personification of Gluttony, and the present Catherine had to be killed in order to defeat her (it was another plan to get out of playing Catherine due to certain circumstances). It didn't happen, ultimately proving that Tropes Are Not Bad.
Etheru states that he planned on Joey and Catherine acting as foils for one another, but arcadiarika's decision to refuse developing the character any longer shot this possibility down.
At one point, unhappy with the fact that nothing was happening, Lemurian thought up the "Ghost Town arc", where the characters would be dropped in a desolate town without food, water, or their powers for a week. The arc was discarded when a player pointed out that the arc wasn't proving anything, because it was almost exactly like what Lemurian was complaining about: Nothing happening.
Midna, at one point, took a break, to try and get his mind off the game for a while, but was banned during the break. It makes one wonder if he really would have improved or would have just kept his bad habits.
And yet another arcadiarika one: in both the Him and Terumi arcs, Catherine would have been the peacemaker of the group, trying to keep them from killing themselves. Unfortunately, it didn't happen. It gets worse—it would have been one of the moments where her character would be positively developed.
Meta Application: Sometimes people tend to bring concepts that weren't used in the source in the game.
"The New Homunculi arc", in which a Composite Character version of Father and Hohenheim creates Homunculi, but forcibly puts Homunculi into members of the group. They would be representing a particular sin (Mega Man, in particular, was planned to be Pride, due to the fact that he's very proud of his achievements). Etheru discarded it, due to having no idea what to do with the arc in question, but he gave it to someone else.
Once in a while, some characters talk about their fears.
What the Hell, Hero? - Everyone, after Osaka accidentally shot Irene in the foot (with a very powerful gun, to boot).
This is the default reaction of the saner members of the Group (i.e., everyone else) whenever Caim does what he does. This is Played for Laughs.
The Worf Effect - Duo. He's pointed out that he's incredibly powerful at times, but he has the uncanny tendency to get blown apart.
Writer on Board - One example would be Andros telling the group how the Touhoumons aren't cute, want to take over the world, etc. all because arcadiarika didn't like them (at first). And then there were the times where the Graysons were used to voice the writer's negative feelings.
Midna used his characters to voice opinions about Mana, among others. This is partially why he's considered a bad roleplayer.
The Writer, one of Lemurian's characters (and also Lemurian himself), was a bit... vocal in his views.
This sometimes happens with Daionusthe23rd. He's gotten better about it, though.
Sometimes players (usually new and/or if it's Arcadiarika) will get the idea to just kill one of their characters pointlessly and/or anticlimactically due to poor reception, which is usually regarded as an unnecessary way to get rid of them, as there are many different ways to remove them without killing them.
Yaoi Fangirl - Yanmie got very turned on by seeing Enker and Ty kissing, and once tried to find Leeron's stash of doujinshi.
Tsubaki Yayoi gets a nosebleed after seeing a doujinshi of Rai and Konoe. She even thinks it's "hot".
Your Worst Nightmare - Rockurtle was afflicted with this about as soon as she was introduced.
Waldorf: I can't believe it. An entire page, and we don't get mentioned once! Statler: Yeah... should you thank them or should I? Both: Do-ho-ho-ho-hoh!