A Marvel ComicsCrisis Crossover for the year 2012, Avengers vs. X-Men (or AvX) is a 12-issue Maxi series with Brian Michael Bendis, Jason Aaron, Matt Fraction, Ed Brubaker and Jonathan Hickman, scripting and John Romita Jr, Oliver Coipel and Adam Kubert for art.The newest Nova crash-lands on Earth, warning vaguely of oncoming doom before lapsing into a coma. Based off the energy signature on his uniform, The Avengers deduce that the warning is about the approaching return of the Phoenix Force, which is heading to Earth to choose a new host, with teenage Mutant messiah Hope Summers being the prime candidate.The X-Men suspect Hope to be the next host of the Phoenix as well, and, under the direction of Cyclops, those on Utopia are attempting to train her to be ready to take on the power. Cyclops believes she will be able to reverse the damage done to the world's mutant population at the end of House of M. But Hope believes she is already ready, having trained for much of her life with her adopted father Cable in the future for the purpose of saving mutantkind.The Avengers feel they need to secure Hope and take her off the planet in order to prevent another Jean Grey (or a Planetary/Species extinction event). The X-Men, naturally, will hold onto Hope at all costs, and therein lies the conflict between the world's most powerful superheroes with the fate of the world hanging in the balance.Before the main series officially kicked off, a Jeph Loeb penned Avengers: X-Sanction mini starring Cable and #0 issue by Brian Bendis and Jason Aaron focusing on Hope Summers and Scarlet Witch were released; and The Avengers: The Children's Crusade series, whilst not billed as part of the event, established the increasing tensions between the Avengers and X-Men whilst dealing with the fall-out of the Scarlet Witch's actions in House of M and Avengers Disassembled. The only non-ongoing tie-in mini series released alongside the main book, was titled AvX: VS, which was focused on showing the battles between individual characters from the Avengers and X-Men that didn't make the main book.
Avengers vs. X-Men provides examples of the following tropes:
All There in the Manual: The main series and some of the tie-ins had online content available to readers with smart phones. Some of it just expounded on the events of the series, showing the events from the points of view of characters whose experiences readers of the paper editions weren't privy to - but at least one tie in actually had a large portion of the dialogue only readable to users of Marvel's smart phone app (or those who can read Cyrillic!).
Back from the Brink: Thanks to the efforts of Scarlet Witch and Hope, this happens to the entire mutant race, due to the reactivation of the mutant gene from the destruction of the Phoenix Force.
Because I Said So: The High Priest of Wakanda grants Black Panther an annullment of his marriage with Storm. The High Priest being Black Panther himself.
Berserk Button: Many buttons were pressed during the story. Storm when Black Panther revealed he had plans to stop her powers (Which, considering how Shadow King loves playing Grand Theft Me on her, you have to admit is reasonable), Rogue and the other X-Teachers when She-Hulk injured Hellion and Glob Herman (Who were attacking her), Moon Knight when Frenzy called him Marc Spector and X-23 and the rest of Avengers Academy when Emma Frost came to destroy Juston's Sentinel. The event was a big button smashing event overall.
Big Bad: The Phoenix Force, which manipulates the majority of the Phoenix Five. Subverted however, while it indeed layed waste to other planets who reached a evolutionary dead end (which, as cruel as it sounds, is it's job) it originally was not there to destroy Earth, all it wanted was to reignite the X-Gen. Things went downhill because it was repedeatly attacked. Captain America even admitted that.
Bittersweet Ending: Cyclops kills Charles Xavier, the closest thing he had to a father, and several of the X-Men are wanted criminals for their actions during the event. However, Hope and the Scarlet Witch were able to use their powers to get rid the Phoenix Force, with the unexpected side effect of undoing the effects of M-Day and reactivating the mutant gene; Captain America admits that Cyclops was right when he accused the Avengers of not doing enough to help the mutant race after M-Day, and subsequently the X-Men are officially endorsed by the Avengers.
Bullying a Dragon: The very reason why the Phoenix Five went insane. Even after making the world a better place and helping the Avengers on several occasions, the latter still thought it was a good idea to repeatedly assault them. When somebody is being possessed by a cosmic Entity that amplifies emotions (especially negative ones) and is capable of annihilating entire universes, this is not the brightest thing to do.
Bystander Syndrome: When Captain America calls together the Illuminati in order to find a way to deal with the Phoenix Five, Reed Richards categorically states that his family are staying out this because they didn't want to take sides between friends of his family, and because it was down to the Avengers that the Phoenix Five are even a problem.
Call Back: When Cyclops gains the full power of the Phoenix, he utters the same phrase that was said when Jean Grey was first thought to be the Phoenix.
The Chosen One: Hope Summers had been speculated in-universe to be one for years. As it turns out, she is.
As of the first two acts, most mutants consider Logan and Beast this since they are siding with the Avengers against the rest of the mutant race, especially given their past and current relationships with Cyclops.
Quicksilver also. Magneto (Quicksilver's father, no less) even refers to those 3 as "Benedict Arnolds of our time".
The fighting started when Captain America turned up on Utopia and told Cyclops that, regardless of the X-Men's opposition, the Avengers were going to take Hope off-world in the event she couldn't control the Phoenix Force. Cyclops responded by optic blasting Captain America off Utopia, and prompting him to call in the rest of the Avengers to start fighting. The entire mess would've been avoided if the two leaders of the superhero and mutant communities had actually talked things over like adults.
It's pretty much being volleyed back and forth between the two teams like its an Olympic sport. There are plenty of fights that could have been easily averted if both sides just acted maturely and rationally like actual adults.
Lampshaded at the end by Captain America, who realizes that he should've done more to improve mutant/human relations so that these events could have been averted.
Wolverine having to choose between siding with the Avengers, or with the X-Men despite disagreeing with Cyclops and his actions of late. Beast and Storm also face this decision, but Beast goes with the Avengers away team and Storm decides to go with the X-Men without a moment's thought.
Averted with Namor, who says via inner monologue that he has decided to side with the X-Men because he admires Cyclops for standing up to his "oppressors", not because he himself is a mutant.
Covers Always Lie: The cover of the final issue would have you believe that Iron Man saves the day against the Phoenix, after being juiced up on cosmic power by Hope and Wanda. Tony is a minor character in the issue, and Hope and Wanda do the day-saving themselves.
Crystal Spires and Togas: What Utopia becomes under the Phoenix Five and what they plan to do for the rest of the world.
Curb-Stomp Battle: Several fights are just immensely one-sided... like Spider-Man vs Juggernaut-powered Colossus, and then the initial confrontation between the Avengers and the Phoenix Five. Spider-Man vs Phoenix!Colossus and Phoenix!Magik is another example that had the former nearly beaten to death before escaping.
Expendable Clone: Mister Sinister invokes this to the nth degree in a tie-in issue dedicated to him. He has an army of mutant clones that he plans to unleash on the Phoenix Five when they inevitably show up to take him down. Not to mention all the clones of himself that he has.
Foreshadowing: In issue 9; Spider-Man tells Hope, anxious to get into action against the Phoenix Five, that being an Avenger means that whilst you may not be at the centre of the action all the time, you need to be ready to step up to the plate. Later in the issue, Spider-Man steps up to allow the rest of the Avengers to rescue their captured team mates. It also serves as a Lampshade Hanging on Spider-Man's background role in the majority of Marvel's Crisis Crossovers since first joining the New Avengers.
Godzilla Threshold: In AvX #11 Captain America basically goes out to the desert with the rest of the X-Men and Avengers still available to ask the Incredible Hulk to assist them in taking down Cyclops. He more or less tells him that he's at the end of his rope and that while he normally wouldn't try to bother him, Phoenix!Cyclops has become so much of a threat that he needs everyone with massive firepower on the team. Hulk's response? "Yes, Hulk will smash for you."
Good Versus Good: The Avengers and the X-Men are both desperate to safely deal with the Phoenix Force and save lives, but they have drastically different ideas on how to do it.
Gratuitous Russian: When Black Widow and Magik fight on the Blue Area of the Moon (just before the Phoenix is torn apart by Iron Man), their dialogue switches back and forth between English and Russian in a quite liberal way.
Hell on Earth: Magik brings a portion of Limbo to Earth and uses it as a prison for the captured Avengers.
Averted by Emma Frost, who is shown to be arrested in New Avengers #30, which is set after AvX.
Averted by Cyclops, who is placed in S.H.I.E.L.D. custody after the final battle, forcing him to live with the guilt of nearly destroying Earth and killing the closest thing he had to a father. He accepts this as he regrets what he did as the Dark Phoenix.
Averted by Namor and, oddly enough Storm, as Wakanda has declared war on Atlantis for its destruction and, because Storm was part of that banner, she is now a wanted criminal. At the same time, the X-Men aren't too wanted there, either, as Logan and the Jean Grey School kids are chased out at the same time.
Martyr Without a Cause: During AvX Consequences, Wolverine finds out that Cyclops wants to die. Why? So he can become the martyr for the revived mutant race. He doesn't.
Maybe Magic, Maybe Mundane: Jason Aaron's endnotes offer three possible identities for the apparition of Jean Scott saw in the final issue. It could be either the real Jean speaking from the Phoenix's plane, the Phoenix itself undergoing a Heel Realization, or simply Scott's mind working things out for itself and using Jean as a cipher.
Missed the Call: In issue 5, after coming in closer contact to the Phoenix Force, Hope Summers realises that she can't handle it and during her hesitation, a Tony Stark/Hank Pym invention intended to destroy the Phoenix Force ends up splitting it apart and causing the creation of the Phoenix Five.
In A-Babies vs. X-Babies, Baby Thor is seen riding Baby Beta Ray Bill, using the same designs from Thor and the Warriors Four. Considering that Bill wasn't involved in the main story (and isn't even an Avenger), this was Gurihiru making a Shout-Out to their own work.
The Avengers accidentally split the Phoenix power five ways between Cyclops, Emma Frost, Namor, Colossus and Magik.
Reed Richards gives one to Captain America and the Illuminati in New Avengers #27.
Reed Richards: This isn't someone out out to ruin us. They are friends and they are making things better. The only ones getting hurt here are you because you keep poking them with a stick.''
The Phoenix Five and associated X-Men didn't show any signs of aggression towards the Avengers until they abducted Hope in issue 5, prompting Cyclops to declare all out war on them, which it could be argued leads towards the Phoenix Five's corruption and rapid degradation towards madness.
"No more Avengers."
Not Himself: Both Aaron and Editor-in-Chief Alonso have strongly implied in interviews that any villainous actions done by the Phoenix Five are to be ascribed to the Phoenix itself and not the character it is possessing. Xavier also hints at this in issue 10.
Not Quite Dead: As expected, the Phoenix has returned by now, shown manifesting in both the young version of Jean and Quentin Quire, which is logical, being a cosmic Force of Life and Death.
Not So Different: Captain America experiences this during a conversation with Hope:
Hope: Do you have any idea what it's like to feel all your life like you're destined for something great, but you can never quite get there? Almost like... Like you're something strong trapped in the body of a weakling?
Cap: I... have some idea what you mean.
Offscreen Moment of Awesome: The Phoenix Five's takeover of the world, during which they supposedly turn it into a utopia, happens during the time skip. Only a little of aftermath is ever seen.
Cable after miraculously surviving his last Heroic Sacrifice, winds up in a future where the world is destroyed and his body is breaking down. Blaquesmith, one of his close friends, tells him that the world ends up this way because of something the Avengers do to Hope. Cable decides to travel back in time to capture and nearly kill the Avengers in his last 24 hours of life, rather than explain the situation or have Blaquesmith do so.
Most if not all of the characters suffer from this, with Cyclops and Captain America probably being the most obvious victims of this trope.
Pyrrhic Victory: Attempted to be invoked by Cyclops, as at the end of the day the effects of M-Day have been undone and ties between the mutant and superhero communities have been strengthened. Captain America counters this in a What the Hell, Hero? moment (See below).
Reed Richards Is Useless: Zig-zagged — After Cyclops, Emma Frost, Namor, Colossus and Magik become the Phoenix Five, they proceed to use their new powers to make the world into a utopia by eradicating famine and disease; but they don't even attempt to restore the Mutant Gene, which was the entire reason Cyclops believed the Phoenix was needed in the first place. Word of God states that this was beyond their power, but they just forgot to put it in the book. As for Reed himself, well, he could assist but chooses not to because he thinks the whole thing is stupid.
Refusal of the Call: Inverted in issue 11, when Hope tells Scott that she's ready to control the Phoenix Force. However, Scott tells her it's too late — she had her chance and she blew it, and it's the Phoenix Five's turn now.
Resistance As Planned: Mr. Sinister, who has created his own society of perfect clones, where even the resistance is part of the system.
Sacrificial Planet: Similarly, in the lead-up the Phoenix Force destroys all sentient life on several inhabited worlds while headed towards Earth.
Screw This, I'm Outta Here!: When the Phoenix Five start going about improving the world and Captain America is still intent on taking them down, Beast gets so upset at Cap's (and Wolverine's) persistence that he up and leaves them.
Shoot the Dog: Wolverine believes Hope needs to be killed to stop the Phoenix. This puts him at odds with the Avengers, since they only want to take her somewhere safe off-world. This is ultimately averted, as in a tie-in Wolverine realizes that even with everything at stake, he'll never truly be able to kill Hope because he views her as a child, one of the few things Logan will never harm.
Spotlight-Stealing Squad: The Avengers. They've been the view point characters and got the most sympathetic treatment. The only X-Men that have gotten any focus are the Phoenix Force Five and those who choose to defect to The Avengers.
Status Quo Is God: By the end of Consequences, we're back to where we were prior to House of M: Mutantkind hated and feared by humanity. They just can't get a break.
Superman Stays Out of Gotham: Invoked. Once the "war" starts the X-Men accuse the Avengers of never caring about mutants because they never took an active stance against the mess that Mutants have had to face since M-Day, which involves several wholesale genocide attempts, which include a school bus full of dead children, and Mutantkind in general being forced onto an isolated Island to prevent themselves being subjected to legislation that was meant to restrict them from having children.
Supporting Protagonist: While the Avengers are the viewpoint characters and (probably) who we were intended to root for, it becomes quite apparent by the end that that's all they are, and the true protagonist and central character of the story and indeed the entire Myth Arc preceding it is Tragic Hero Cyclops. A decent argument could also be made for Scarlet Witch being the actual main character, as well.
Take Our Word for It: Very little of the Phoenix Five's utopian world is actually shown, and by the time we do start to see hints of what they've done, the conflict with the Avengers and the Phoenix possession is already driving them over the edge.
Tragic Hero: Scott and Emma by the end. While Emma does terrible things, she's also horrified by her actions. Colossus could also qualify due to being set up for a fall by his sister. By contrast, Namor is the Holier Than ThouJerkass he's always been (but with cosmic power this time) and Magik turned out to be a straight-up villain.
With Great Power Comes Great Insanity: With the checks to their behavior gone and their emotions being amplified, the Phoenix Five grow ever closer to going over the edge. As of Issue #9, Cyclops is the only one still holding it together. However, by Issue #11, he's gone fully Dark Phoenix.
Utopia Justifies the Means: The justification the X-Men use when called out on their more morally gray actions or met with opposition. The Phoenix Five X-Men are building a utopia on Earth free of war, hunger, and persecution, so who in their right mind would be against that? Rachel even says "Why would you want to stand in the way of true utopia?"
What If?: A 4-issue What if series where Magneto trains Hope instead and Logan kills Storm by "accident" in the helicarrier and escalate events early. It ends with everyone on Earth and the Guardians of the Galaxy dead except Wolverine, who reunites with a Phoenix Force-empowered Jean Grey to breathe life into the world again.
What Have I Become?: Colossus has a moment of this when he accidentally burns his love interest Kitty Pride in a brief rage.
Captain America: Don't you dare! Don't you dare try and turn this into a win! You waged a war that set friend against friend! You played Russian Roulette with the planet! You left wounds that will take years to heal, if they ever heal at all. And you killed one of the finest men I've ever known. If you consider that a win... I pity you. I really do.
An incarcerated Scott fires one right back at Logan in Consequences, pointing out that his plan to murder Hope to stop the Phoenix would have basically doomed everyone had he succeeded.
Why Did You Make Me Hit You?: After Cyclops kills Xavier, he breaks down crying and blames Captain America and the Avengers for it. Whether his accusation has a point (like Hawkeye's arrow on his neck had point) or if this was just further proof that Scott was just falling further off the edge is up to the reader.
Wolverine, a long-standing X-Man but at the same time an established Avenger currently on bad terms with Cyclops.
A promotional comic which listed the sides and teams of the battle listed Quicksilver, Scarlet Witch, Nova, Deadpool, Savage Hulk and Cable as wild cards. Quicksilver and Scarlet Witch both rejoin the Avengers before the halfway point; Hulk finally shows up in Issue #11; Nova crash lands in New York in the first issue, avoids the majority of the fighting and only appears again in Issue #12; and neither Deadpool nor Cable play any part in the event itself.
The Worf Effect: While the battle wages back and forth first, all the characters safe the Scarlet Witch and Hope (even the heavy hitters like Thor and Hulk) repedeatly get their asses handed to them by the newly created Phoenix 5 in almost hilariously one-sided battles.
Working with the Ex: After Storm defects from the X-Men to help the Avengers, she's swiftly told by Black Panther that due to her association with the Phoenix Five (One of whom had just flooded Wakanda in a fit of rage), the High Priest of Wakanda has granted T'Challa an annullment of their marriage. The High Priest being T'Challa himself. However, with Storm actively working with Black Panther to save the captured Avengers, its possible this might be averted. As of A+X, they have officially separated.
After Cyclops says that Phoenix could be used to "put the world back on track", Magneto points that Cyclops is starting to sound like him. It turns out this is a Berserk Button for Cyclops when this happens one too many times. For a while, people have been saying this to him when he gets particularly protective of mutant kind, and this bit is essentially him spitting back. But, as he's now Phoenix powered and as such insane, he replies that the difference is "he's winning".
Averted with Wolverine in a tie-in when he says in narration that when he looks at the Jean Grey Expy, Hope. He doesn't see that strong woman he loved, but just a child who has no idea what she's gotten herself into.
After hearing Captain America justify his actions, Iron Man claims that he sounds just like himself when the Captain opposed him during Civil War.
Iron Man lets Cap have it again when Cap calls together the Illuminati in an attempt to figure out what to do.