.hack comprises "Project .hack" and ".hack Conglomerate". It is a Japanese multimedia franchise primarily developed by CyberConnect2 and published by Bandai. The franchise is set on an Earth with an alternate history. In this timeline, a new version of the Internet arises following a major global computer network disaster in 2005. Central to the premise is a mystery about the wildly popular in-universe video game, The World. As most of the story takes place within The World, characters typically play and interact as their avatars.

The first four video games follow a newcomer called Kite, who goes on a quest to revive his friend, who fell into a coma after his character was killed by an unknown creature. Bee Train also produced an anime series focused on a player named Tsukasa, who has no memory of his identity outside of the game and cannot leave The World. In 2006, Cyber Connect 2 and Bee Train produced two new series: .hack//G.U. and .hack//Roots. The two series involve a returning player by the name of Haseo who, after the loss of his guild, goes on a quest to find the player killer (PK) Tri-Edge who sent his friend Shino into a coma. The latest game by CyberConnect2 is .hack//Link, where Tokio Kuryuu is transported into The World: RX and time-travels across the previous storylines to restore frozen players.

.hack was conceived by CyberConnect2 with the idea of creating a fictional MMORPG in order to simulate a realistic story. The initial characters were designed by Yoshiyuki Sadamoto, while later installments involved additional artists. The critical reception to the original characters has been positive for their designs and realistic traits. The G.U. characters received mixed responses due to Hero's anti-heroic characterization but praise for his growth.

Creation and design

Development for .hack began in early 2000 with the aim of creating a distinctive product that would shock and surprise the player. CyberConnect2's president, Hiroshi Matsuyama, played a key role in developing the concept for the series. A number of core ideas, including "slaying dragons or being a thief in London" were explored but rejected in favor of an "offline/online game". The developers looked at a number of MMORPGs such as Phantasy Star Online, Ultima Online, and Final Fantasy XI for inspiration, and drew influences from the prior works of character designer Yoshiyuki Sadamoto (Neon Genesis Evangelion) and scenario writer Kazunori Itō (Ghost in the Shell). Matsuyama stated that the team was proud of having Sadamoto design the cast, despite his lack of previous involvement in gaming, and said that working with him was a great opportunity. Itō noted that casting the player into the role of a subscriber to The World creates a unique story-telling situation that draws the player deeper into the plot.

Sadamoto's character designs follow the fantasy theme, drawing influence from the sword and sorcery subgenre in particular. Character designs also draw on Celtic imagery: Director Mashimo acknowledged similarities between Bear's design and William Wallace from Braveheart, an example of a Celtic warrior. All the characters are given distinctive patterns resembling tattoos that represent Wave, an aspect of the fictional gameplay.

Seiichiro Hosokawa was the lead artist for the .hack//G.U. game trilogy. While CyberConnect2 designed the characters for .hack//G.U., Sadamoto returned as supervisor. As a result, some aesthetics from Haseo's character design featured in the original trailers were removed from the finished product. The trilogy also made a major change by distancing the protagonist, Haseo, from the player in an effort to appeal more to players.

Main characters

The World The following is a list of the main characters from the first version of the massively multiplayer online role-playing game The World: is an advanced AI that takes the form of a young girl whose white hair, skin, and garments give her a ghostly appearance. She was created by Harald Hoerwick to be a symbol of the daughter he could have had with his deceased lover. She is the perfect AI and the spirit of The World. Since her awakening by Tsukasa, she has been fleeing the clutches of Skeith, as witnessed by Orca, Kite, and several other fictional players. She intends to take in and collect player information by data-draining the current AI control program, Morganna. In response, Morganna intentionally keeps Aura in her sleep-like state. After Morganna's plot to keep Aura asleep by using Tsukasa in .hack//Sign fails, Aura awakens and becomes hunted by Morganna's phases to prevent her from developing Data Drain. Aura manages to cultivate this power into an installation book, which is acquired by Kite. Aura becomes data-drained afterward and is scattered throughout The World. She communicates with Kite and other in-game players through corrupted emails, which leads to the defeat of most of the phases. During the final battle, Aura is scattered again and merges with Morganna to complete the Ultimate AI. She becomes an omnipresent yet mostly silent force within The World for some time. She later sets out to perfect herself by giving two in-game players, Shugo and Rena, chibi versions of their avatars, Kite and Blackrose, in a contest and giving birth to another AI, Zefie. This helps Shugo reach his goal of becoming a hero. Aura's eventual disappearance causes the decline of The World. Consequently, the CC Corp develops Project GU to recreate her. is the main character of the first volume of the novel .hack//AI buster and a central character in the second volume. In the fictional game, Albireo is a powerful Long Arm character who mostly keeps to himself as a solo player. Outside of the game, Albireo is Kazushi Watarai, a system administrator and debugger for CC Corporation. His job is to work out any glitches in the game and delete any system anomalies. He hunts vagrant AI Lycoris as part of his job, though he later meets and befriends her, unaware of her true nature. With the help of newbie player Hokuto, he helps her regain various pieces of data; when completed, Lycoris realizes that she cannot continue to exist and forces Albireo to delete her. Albireo reappears in .hack//AI buster 2, chasing after Tsukasa, though he soon runs into Macha and is rendered comatose for several months. He is forced to resign from CC Corporation as he is blamed for causing the Twilight Incident. He then meets Hokuto's player, Haruka Mizuhara, and they begin a live-in relationship. , also referred to as Lord Balmung and "Balmung of the Azure Sky", is a legendary player in The World. He earned fame with his Blademaster character by defeating the game event One Sin, which was thought unbeatable, with his partner Orca, causing them to be known as "The Descendants of Fianna". Balmung received his title and white wings, which allow his avatar to float and jump higher than other characters. Balmung truly loves The World and plays it very seriously. He is formal and assertive in his views and sometimes appears arrogant. He follows a strict moral code of doing good in The World, investigates disturbances, and refuses to associate with .hackers. In .hack//Legend of the Twilight, he is much more carefree with new players, though completely businesslike with his associates. ; Doug Erholtz (.hack//Infection) is a large, burly Blademaster. He wears relatively little clothing, and most of his body and face are covered in blue wave tattoos resembling Celtic woad. Having played computer games for over thirty years, he uses The World to relax while helping new players and to interact with his estranged son. He enjoys interacting with Mimiru and BT, having met BT in person. Outside of the game, he is a famous novelist named and enjoys reading and going to the theater. He later becomes the guardian of An Shouji, the player behind Tsukasa, and supports her financially as she attends boarding school. is a female heavy blade with a tough-as-nails attitude who can be a bit full of herself at times. Clashing with Kite, she attempts to conceal that she's as new to the game as he is. They gradually warm up to each other, and Kite balances her shortcomings. She is searching for a cure for her brother, who was put in a coma by a data bug. Outside the game, she is a tennis player and high-school student named Akira Hayami. BT is a Wavemaster featured in .hack//Sign. Her avatar has blonde hair and dresses in light green robes. BT focuses her attention on finding the "Key of the Twilight" and seems unconcerned with Tsukasa's predicament. She often meets with Bear and Crim both online and in person. The name BT comes from her favorite food, a BLT sandwich, but without the lettuce, which she hates.BT: "It's lettuce." Tsukasa: "Lettuce?" BT: "There's not enough taste to dislike it, and there's not smell to it. Most people say that. But I dislike it because I dislike it." .hack//Sign, episode 17, Conflict. Outside the game, she is a former model named Machiko who works at a dispatch company in the Tohoku region. is a long arm featured in .hack//Sign. His avatar is a male with spiky blue hair, a red jacket, flared red and yellow pants, and a wave symbol on his chest. Crim plays as a very happy-go-lucky character, easygoing and sociable. He enjoys testing his skills against strong opponents and is always ready to help anyone in need. He founded the Crimson Knights with Subaru, though he eventually leaves. He is very close to Subaru and knows that she is handicapped. He is a businessman outside the game and frequently makes international business trips. Cubia is a monster in The World, the 'opposite side' of the mystical "Twilight Bracelet", born during its creation. It constantly attempts to prevent Kite from progressing until it is finally defeated, which results in the destruction of the bracelet. .hack//XXXX features Cubia with a human avatar who befriends Kite. Cubia returns in G.U. as the anti-Epitaph, with power equal to all eight Epitaph PCs. It spreads throughout the internet, causing malfunctions worldwide. Elk is a shy Wavemaster who only finds comfort in working with Mia, showing loyalty and concern for her as her condition worsens. He eventually accepts Kite and his companions, and they work together. In the next version of The World, , the player behind Elk, creates the Temptress. Endrance obsessively plays the game, logging off only to sleep, and is cold towards other players while interacting with a small cat, which he believes to be the reincarnation of Mia. The cat is actually an AIDA feeding off his emotions. Haseo destroys the AIDA while fighting Endrance, who falls into a deep depression until he becomes connected to Haseo in a similar format, devoting his life to what he believes he owes. is a quiet Long Arm and a romantic with a great love for flowers, which she shares with Kite. Though she seems mysterious, she is not part of the conspiracy that Kite is battling. Recruiting Gardenia in the game is optional; it is done by reading a message board post from her "groupies" and visiting their meeting place. She resembles the character "Mimika", whom Mimiru saw use "Ap Crystal" in the episode "Intermezzo", but, contrary to popular belief, she is not one of the three players who controlled Mimika.