Heathcliff

Kayaba Akihiko aka Heathcliff is a character from Sword Art Online.

Profile
Heathcliff was the development director and GM (Game Master) of «Sword Art Online». He was also the designer of the «NerveGear», the Cardinal System, and «The Seed», as well as the main antagonist of the Aincrad Arc. He played SAO as the leader of the «Knights of the Blood», Heathcliff.

Background
In his childhood, Akihiko expressed an interest in reading books. He was not particularly engrossed in games and computers, but he participated in the Mathematics Club of his high school. Later on, in university, he did not participate in any circles because he frequently worked in and out of laboratories.

When Akihiko began developing Sword Art Online, he toiled for years to develop the game software. His main goal and dream was to "make Aincrad float" but after he did so, he was not entirely sure what his dreams, aspirations, or purpose were.

Akihiko's love interest was Koujiro Rinko, who assisted him for ten years of the game's development, and took care of his body whenever he had to FullDive during the course of Sword Art Online.

Aincrad Arc
On the first day of Sword Art Online's official service, during which around 10,000 players logged into SAO, Kayaba Akihiko successfully trapped the players in the game. After forcefully teleporting all players in the game to the Town of Beginnings, he appeared in his GM avatar and, during his tutorial, explained the new rules of the game, including the fact that the players would need to conquer all 100 floors of the game to be set free and that death in-game or any attempt to remove the NerveGear would cause the NerveGear to fry the user's brain. To prove that the game was their new reality, Akihiko changed the avatars of all players to look like their real life bodies and then took his leave.

His avatar, Heathcliff, was the leader of what is considered to be the Sword Art Online's strongest guild «Knights of the Blood». He was the owner of the first «Unique Skill» «Holy Sword» and was considered to be strongest player in-game. He wielded the collective one-handed sword and tower shield called Liberator. He also was able to hold off the boss of the 50th Floor for ten minutes by himself, which earned him the title «Man of Legend» (伝説の男, Densetsu no Otoko?). It was also rumored in Sword Art Online that Heathcliff's hit points (HP) had never gone into the yellow zone, which was due to his identity being Kayaba Akihiko and being able to make himself invincible by making his character into an «Immortal Object» after his health reached fifty percent or was about to surpass it.

In the manga, he was first seen at the Town of Beginnings using his avatar, Heathcliff, with the rest of the Sword Art Online players listening to his other self talk about the new rules that made Sword Art Online into a death game. Kirito even commented on how calm Heathcliff's avatar was on the situation.

As a leader of the Knights of the Blood, Heathcliff was quite renowned for his general tendency to stay out of guild affairs, preferring to allow his sub-leaders to develop plans and advance the game. Apart from guild paperwork and battles, Heathcliff rarely interfered with the choices and actions of his sub-leaders. The only exception to this was when Asuna expressed her wish to leave the guild, and Heathcliff refused to allow her do so without challenging Kirito to a duel.

Kirito first suspected his true identity during his match against Heathcliff when Kirito saw that Heathcliff's speed exceeded the system limits. However, Kirito deduced his true identity on the 75th floor. Thanks to a miracle in the game allowing Kirito to launch one final attack after his hit points were depleted, Kirito managed to defeat Heathcliff and free all the trapped players from the death game.

In the aftermath of the death game, Akihiko proceeded with his desire to die along with the collapse of the game, as he had decided before Sword Art Online even began. He thus used a remodeled FullDive machine to perform a super high-powered scan of his brain to transfer his consciousness into the virtual world permanently. This scan led to his brain cells burning out, killing his body.

Fairy Dance Arc
Although the scan only had less than a 1 in 1000 chance of succeeding, apparently the scan was successful, as he reappeared in ALfheim Online, noting that his program was only recently awakened after hearing Kirito's voice during the latter's encounter with Oberon. When Akihiko saw Kirito giving up and submitting to the power of the system, he reminded the Black Swordsman about their battle, where Akihiko was forced to acknowledge the power of the human will, and encouraged Kirito to stand and take hold of his sword. After Kirito stood up and grabbed the fist of Oberon, who attempted to punch him, Akihiko revealed his administrator ID and password to Kirito, allowing him to access Heathcliff's account, which in terms of administrative power, outranked Oberon's and allowed Kirito to easily defeat Oberon. After Oberon was defeated and Asuna logged out, Akihiko returned to Kirito and entrusted him with the «World Seed» as compensation for helping Kirito. Although Akihiko wished to have the seed sprout, he left the choice of what to do with it to Kirito as he disappeared into thin air.

Crossover Appearances
2K10 Anime Battle Coliseum

Heathcliff is one of the DLC characters from Pack 2, and as well, one of the alternative final bosses of the game, the other ones are Dezrath, Zamasu, Dio Brando, Android 21 (Evil), Altair, Lord Boros and Madara Uchiha.

Super X Dimensions

Heathcliff appears as a Boss Unit.

Trivia

 * Akihiko had an annual salary of more than 100 million yen (about 1,090,000.00 USD in August 30, 2013) at the age of 18.
 * Aside from research and development, Akihiko's hobbies were cooking and playing Go (the board game).
 * The first RPG Akihiko played was an old RPG known as Wizardry. It apparently played an influence on the development of Sword Art Online.
 * Akihiko intended to reveal his true identity on Sword Art Online on the 95th floor, and become the final boss on the 100th floor.
 * Akihiko admitted that he would not be able to win against Kirito with his actual reflexes.
 * Akihiko had spared no attention to the existence of Yui and later regretted it, saying that it was a great opportunity that had gone by.
 * The happiest moment to Akihiko during SAO was when Kirito saw through his true identity on the 75th floor, as Akihiko then realized that he (Akihiko) was nothing more than another player.
 * Heathcliff is the only boss in Sword Art Online to have just one HP bar instead of multiple.
 * Akihiko's avatar's name «Heathcliff» is possibly either a reference to Wuthering Heights or Phantasy Star Online.
 * To hide his identity, along with his appearance, it was necessary for him to use his GM administration account to alter his voice. For this plot device, two voice actors were hired to voice him, with his original voice being used in the introduction and after he was discovered by Kirito.
 * In the non-canon game adaptations Infinity Moment and Hollow Fragment, a massive glitch caused by an overload of negative emotions cut Kirito's battle with Heathcliff on the 75th Floor short, and he vanished before Kirito could defeat him. Heathcliff reappeared on the 100th Floor as the final boss of the game. During the narration by Kirito afterwards, it was revealed that Kayaba Akihiko's NerveGear had killed him promptly after the battle on the 75th Floor, possibly meaning that the Heathcliff Kirito fought against was his afterimage.