Guilty Gear X2, subtitled The Midnight Carnival, is the third full installment in the Guilty Gear series of fighting games. First released in 2002, it has since received three updated versions. GGXX furthered the plot of the series and introduced new characters and gameplay mechanics. It also introduced an extremely in-depth story mode exploring the characters' motivations, histories and what they've been up to since the last game. Most of these have three paths that split at crucial battles depending on how they're fought and won. These paths lead to three different endings, some canonical, some not.
Picking up two weeks after the events of Guilty Gear X, Guilty Gear XX's story mode mostly revolves around the machinations of I-No, servant of That Man, or the Post-War Administration Bureau's various plots, most of which involve Robo-Kys. The story exists primarily to set up the conflict between various organizations and characters. It is also the first time That Man plays a significant in-game role, being encountered by almost every character in at least one of their plot strings.
I-no: A maniacally zealous servant of That Man, I-No is a vulgar, sexually charged person who seeks to manipulate the other fighters against each other. She believes she's acting in the best interests of That Man and takes her role very seriously, even though she takes little else seriously. She is vulgar and crude to the other fighters in an attempt to rile them up before setting them against each other. She apparently has the power to time-travel, though cannot do it whenver she wishes because of the immense effort involved. One time she did this to any significance was to save the life of Ky Kiske and thus ensure humanity's victory in the Crusades. She wields an electric guitar and animate witch's hat that both allow her to use music-based attacks. She also derives an inordinate amount of pleasure from tormenting DIzzy, even stalking her onboard the Jellyfish Pirates' ship and knocking her off of it.
Zappa: A young, romantic man who seeks nothing more than a good wife and to write in his diary, a series of letters to his mother. His latest entries mostly center around a strange disease that sees him passing out randomly and waking up in unfamiliar places with horrible injuries and often people lying unconscious around him. Unbeknownst to the poor man, he's been possessed by the malevolent ghost S-Ko, and several lesser ghosts who are also his weapons in combat. These phantasms are: a ghost dog, several Will-O'-Wisps that become more frequent as Zappa connects with more ghostly attacks, three centipedes, the lightning wielding Raou, and a broken sword. S-Ko is apparently sadistic and takes joe in distorting and causing Zappa to fight, while the other spirits actually seem to care for and comfort him. Zappa seeks the mysterious healer Faust to cure him of his apparent sickness.
Bridget: A young boy wearing a nun's habit, Bridget is incredibly androgynous and often mistaken for a young woman. This fact embarasses Bridget to no end and he joins the latest tournament to prove himself a man and a worthy bounty hunter. I-No gives him a list of people she claims all have bounties on their heads, but who are actually other people in the tournament and Bridget sets off to bring them all to "justice." He wields a yo-yo as his weapon, but can also conjur a mechanical teddy bear named Roger with several different powers himself.
Slayer: A vampire and founder of the Assassin's Guild, Slayer slept through many of the events of the first Guilty Gear games, but awoke after sensing his guild fall to chaos after Zato-1's death and disappearance. Slayer is extremely cultured and well-mannered, even treating his opponent cordially as he defeats them. He greatly enjoys writing and performing haiku and travels with his immortal wife Sharon. He has a conncetion to Gabriel and may have even helped in the overthrow of Zepp. His power is so great that even That Man shows him deference and Slayer has a connection to Sol Badguy as well, possibly from Sol having lived so long. He fights with his bare hands, but his vampiric strength and supernatural abilities more than make up for his lack of weaponry.
Zato-1/Eddie: Millia Rage put Zato out of his misery at the end of the last game, but this act of mercy unwittingly allowed Eddie to take complete control over Zato's remains. The body, however, is quickly deteriorating and Eddie is constantly searching for a worthy host to take over, preferrably one with a pulse. These events brought the founder of the Assassin's Guild, Slayer, out of his sleep.
Venom: Realizing the error his actions in the last game, Venom has finally come to grips with the fact that his friend and mentor, Zato-1, is truly dead. He now seeks to stop Eddie from sullying Zato's name even further, going through any means to accomplish this goal and even showing his fighting prowess to Slayer.
Millia Rage: After killing Zato-1, Millia returned to her solitary life. However, she heard rumors of a new menace using powers similar to Zato's. She sets out seeking closure and bringing an end to the saga of her love. In one ending, Slayer reveals that her hair is a similar being to Eddie: a parasitic organism that may one day begin to overpower her will. Millia reveals that she knew this all along and has been wrestling with the beast for years. She blasts through Slayer to Eddie, in another two endings, and kills the creature once and for all, in one ending leaving her creature on Zato's grave as a memorial.
Sol Badguy: Sol immediately begins persuing I-No, knowing that she is a crucial link in finding That Man. In his story mode, it is revealed that Sol has begun a rather awkward friendship with Axl and has begun training him to become a better fighter. I-No leads Sol through a series of battles, finally culminating with Sol unleashing his full power, revealing his nature as a GEAR having lived for hundreds of years, and defeating the vulgar woman. This leads amounts to nothing, however, as That Man easily defeats Sol, but allows him to live as he still has a vital role to play. In another ending, Slayer reveals that the sinister Post-War Administration Bureau is extremely interested in Dizzy and weaponizing her.
Ky Kiske: Having confirmed that Dizzy is no threat to humanity, Ky Kiske entrusted her to Johnny and the Jellyfish Pirates and returned to his duty as commander of the Holy Order. However, he soon begins to hear rumors of wicked doings perpetrated by someone who looks like him. This turns out to be the Robo-Ky army let loose by the Post-War Administration Bureau, but also involves the mysterious That Man, I-No, his rival Sol and more secrets that make him question his role in the world.
Potemkin: Having been informed of Dizzy's predicament by Slayer, Potemkin goes on a search for the wayward GEAR. He eventually becomes entangled in the machinations of the Post-War Administration Bureau. Eventually finding Dizzy, Potemkin is hesitant to let her return to Johnny after being nearly killed from the fall, he eventually relents and allows her to return home. Another ending involves battle Briget over Dizzy, and the final one involves him taking on an entire army of Robo-Kys.
Testament: Having gained an uneasy acceptance of humanity, Testament goes to the Jellyfish Pirateship to visit Dizzy, only to find out she'd been knocked off moments earlier by the vicious I-No. Testament curses humanity for their persecution and goes to seek his dear friend. In one, non-canonical, ending Dizzy is killed and Testament vows war against humanity. Either or both of the other endings could be canonical: in the first he encounters Sol and reveals a deep seated respect for him since Sol can understand the pain that Testament endures. In the third ending, Dizzy is brought back to consciousness, but assures him that the Pirates were not responsible for her predicament. Testament regains his grudging acceptance of humanity.
May: After I-No knocks Dizzy from the ship she lived on, May goes in persuit of her new friend. In one interaction, she encounters Dr. Faust, whom she attacks after he attempts to calm her incredible fear of bald men. In her other endings, she is reunited with her friend, and they return to the ship. It is revealed, if Justice defeats May in Arcade Mode, that May is of Japanese descent and thus quite a rarity in the Guilty Gear universe.
Johnny: Having acquired a new crew member, Johnny remains very protective of Dizzy, persuing her after I-No's unprovoked attack.
Jam Kuradoberi: Using the prize money from the previous game, Jam opens her restaurante and becomes a tremendous success. The restaurante, sadly, is burned down by a mysterious figure dressed as her crush, Ky Kiske. She is devastated by the loss and battles with the figure, who turns out to be a Robo-Ky. Jam sets out to try and make enough money to repair and start again. In one ending, the Post-War Administration Bureau is revealed to be watching her every move, remarking that her fighting style, which incorpoartes ki energy into it, could be useful in some unknown future conflict. In another one, the Robo-Ky calls in an army, but the real Ky Kiske intervenes, much to Jam's delight. She asks him out to a picnic, claiming that great food will cure whatever is ailing him. In her third ending, she is tricked into hunting Venom, Millia and Johnny after being given a false bounty list by I-No. She invites them all to dinner after the falsehood of the list is revealed, but the two assassin's refuse to reconcile with each other and their fighting knocks over Jam's new stall.
Faust: The mad doctor makes another appearance, encountering I-No early in his story mode and pursuing her to keep her from harming any innocent people. After finally tracking her down and defeating her, I-No taunts the doctor, saying that he still enjoys battle and pain. He admits she's right, but vows to keep his oath to help others. Zappa encounters him in another ending, in the thrall of the phantom who's possesed him, but Faust overcomes the ghost. He also declares Zappa sadly incurable. In his final ending, he learns, during a battle with Venom, that the Assassin's Guild was involved in the death of the young girl that drove Faust mad. The two warriors are then set upon by an army of Robo-Kys and if they survive, Venom says he will reveal everything to Faust.
Dizzy: Having joined the Jellyfish Pirates, Dizzy is enjoying her new, carefree life with people who truly care for her. This is all abruptly ended, however, when the sadistic I-No arrives and does battle with her, knocking her from the ship. Dizzy is forced to cede control of her actions to her more violent aspect Necro. She rampages through several characters until coming upon Dr. Faust, who is able to cure her of her possession. From there, Dizzy's story leads her to either fighting and defeating I-No, which then leads her to encountering That Man, or to Bridget, who attacks Dizzy thinking the bounty on her head is still valid. After the mistake is cleared up, through fighting of course, Dizzy befriends the apologetic Bridget.
Anji Mito: Anji's primary motivation in his story mode is bringing Japan back to being a world power and freeing the people from the government colonies.
Baiken: Baiken continues her quest for revenge, as well as her ancilary quest to avoid Anji at any price.
Chipp Zanuff: Having ventured into the forest to continue his training, Chipp encounters Dizzy, having recently been ejected from her ship and in the clutches of Necro. He battles her and encounters several more characters, including Eddie. Based on that battle, the his path diverges into two separate paths: in one he encounters and defeats Venom, the current leader of the Assassin's Guild, who offers Chipp the chance to lead the guild if he becomes president of the Union. In another ending he encounters Slayer, who sees him as so far beneath him, it wouldn't be worth Slayer's time to kill Chipp. Chipp's final ending revolves around becoming aware of the Post-War Administration Bureau after destroying a Robo-Ky.
Axl Low: Axl is searching for Faust as he believes such a skillful doctor can cure his timeslipping. He has come to friendly terms with Sol, whom he entreats to teach him more about how to fight. From there, he either encounters Faust, who tells him that his timeslips are most likely because there is another version of him running around. He later encounters That Man and the mysterious Raven, who turns out to be the other version of himself. Being in such close proximity to his other self, Axl is thrown through a random time vortex. In another, he unknowingly slips through time and battles Kliff Undersn and even Justice, realizing he's been hurled back in time.