Guilty Gear X (also known as Guilty Gear X: [By Your Side "G.GEAR"]) is a 2D sci-fi fantasy fighting game developed by Arc System Works and released by Sammy for arcades (running Dreamcast-based Sega NAOMI hardware) in Japan on July 2000.
Building on the previous Guilty Gear, Guilty Gear X is the first arcade iteration of the series and features larger, more detailed anime-style graphics (with characters getting re-worked sprites) and updated gameplay mechanics (most notably the introduction of Roman Cancels, allowing players to cancel their special moves into other moves).
Taking place shortly after the events of Guilty Gear (where Sol Badguy, revealed to be the "Guilty Gear", defeats and destroys the powerful Gear Justice), the story follows a new mysterious self-reliant Gear emerging and the Union of Nations putting a bounty on it (for the huge sum of 500,000 World Dollars).
The game was ported to the Dreamcast exclusively in Japan (on December 14, 2000), to the PlayStation 2 in North America (on September 30, 2001), in Japan (on November 29, 2001 as Guilty Gear X Plus), and in Europe (by Virgin Interactive on March 1, 2002), and to the PC exclusively in Japan (by CyberFront on November 30, 2001). A handheld version was released for the Game Boy Advance in Japan (on January 5, 2002), in North America (on August 13, 2002), and in Europe (on September 27, 2002).
The arcade version later received a re-release for the Dreamcast-based Atomiswave hardware exclusively in Japan in 2003, adding the Survival game mode from the console versions and the boss characters playable from the start.
The game is fundamentally identical to the first Guilty Gear, with one notable exception: the DESTRUCTION moves no longer end the fight absolutely, only the round in which they connect. The game features the same frantic pacing, combos and air-combos as it's predecessor with a new mechanic of a knock-down attack that can be used to interrupt combos as long as the meter is filled as well as the Roman Guard, which prevents damage from special attacks at the cost of draining the tension gauge as long as it's active.
Most of the characters from the original Guilty Gear return, with 4 new playable characters and 1 new final boss. Kliff Undersn and Justice do not make a return, although they are later added in the PS2 version as hidden unlockables. Baiken, formerly a hidden boss, makes her debut in the starting roster.
There are a total of 16 fighters (18 in the PS2 version).
- Johnny - An American bandit and the leader of a band of chivalrous pirates. A fierce womanizer, his crew is comprised solely of women. He fights with a Japanese-style wooden sword.
- Anji Mito - One of the few full-blooded Japanese left alive after Japan's destruction during the Crusades, Anji decides to conceal his origins and search for the one responsible for the destruction of his homeland: the creator of the Gears, known as "The Man". He fights with a pair of hand-held fans.
- Jam Kuradoberi - An aspiring Chinese chef who aims to become famous in the Chinese culinary world. She seeks to use the bounty to secure funds for her own restaurant. Unlike other fighters, she fights solely with martial arts.
- Venom - A British orphan who was adopted by a group of assassins led by Zato-1. With Zato failing to return to the guild after the tournament, Venom investigates a possible Zato sighting. He fights using a pool cue and magical billiard balls.
- Dizzy (final boss, unlockable in console versions and playable from the start in the Atomiswave revision) - A mysterious self-reliant Gear who is believed to have no intention on hurting humans.
- Sol Badguy - Revealed in the last tournament to be the titular "Guilty Gear", Sol was the subject of bio-mechanical weapon research only to live through the Crusades as an American bounty hunter targeting other Gears. After defeating the self-reliant Gear Justice and hiding for a year, he sets off to investigate the news of a new self-reliant Gear.
- Ky Kiske - A talented French swordsman and the former young leader of the Sacred Order of Holy Knights. While investigating the tournament, he begins to question his sense of justice and the belief that all Gears are evil. Hearing that a new self-reliant Gear has no intention on hurting humans, he sets off to investigate. In the console-exclusive "Guilty Gear Mode", Ky acts in a mysterious robotic fashion (which later becomes the base for Robo-Ky).
- Millia Rage - A Russian orphan who was adopted by a group of assassins and trained to use her hair as a lethal weapon, only to betray the organization and its leader: Zato-1. After defeating Zato in the tournament, she develops complex feelings about the battle and, once Zato has been sighted, decides to hunt him down once and for all.
- Zato-1 - A mysterious Spanish assassin who becomes the leader of a group of assassins after invoking forbidden arts (sacrificing his sight for the ability to control his shadow). After his defeat from Millia Rage in the tournament, his shadow seized control of his body and begins seeking out its brethren.
- Potemkin - Formerly a slave soldier of the airborne military empire of Zepp (which, thanks to him during the tournament, becomes a peaceful civilization), Potemkin is given orders from the President of Zepp to safely recover the Gear being pursued.
- Faust - Formerly known as Dr. Baldhead, Faust is a brilliant Chinese physician who became a serial killer after being driven mad (as a girl under his care died mysteriously under his scalpel). During the tournament, he managed to regain his humanity and realized that it was someone else who caused the mishap. Donning a paper bag to forge a new identity, he now seeks the truth.
- Chipp Zanuff - An American ninja who strived for revenge against the mysterious group that murdered his master Tsuyoshi. During the tournament, he realizes he lacked devotion and decides to go back into training and finding his destiny.
- May - A cheerful young orphan who was adopted by a group of pirates led by the daring Johnny (who she develops a fierce crush on). Her goal is to use the bounty to buy Johnny a birthday gift.
- Axl Low - A 20th-century British hoodlum who was caught in a mysterious "time slip" and hurtled two centuries into the future. After years of searching for a way back home, he learns of another time traveler known as "The Man" and, believing that this person is affiliated with the Gear incident, searches for him.
- Baiken - A mysterious Japanese swordswoman who, despite missing her right arm and left eye, uses a variety of hidden weapons she carries in her unused sleeve. She searches for "The Man", who she believes was responsible for the Gears raid in her homeland.
- Testament (sub-boss, unlockable in console versions and playable from the start in the Atomiswave revision) - A mysterious Gear who was revealed to be the mastermind behind the tournament as a way to free the powerful Gear known as Justice. Little is known about his whereabouts after Justice's destruction.
- Justice (hidden unlockable, added in the PS2 version)