Kazuya Mishima

Kazuya Mishima is one of the main characters in the Tekken series. He appears in all Tekken games except Tekken 3, in which he only made two cameo appearances. Although he is seen as the main protagonist and hero of the first Tekken game, Kazuya became one of the major antagonists of the series ever since Tekken 2. Most importantly, Kazuya is the son of Heihachi Mishima and Kazumi Mishima, the possible love interest of Jun Kazama and the father of Jin Kazama. He's also the half-brother of Lars Alexandersson, the adoptive brother of Lee Chaolan, and the grandson of Jinpachi Mishima.

Story
At five years of age, Kazuya finds out his mother died at the hands of his father and attempts to get revenge against him. However, Kazuya is defeated almost immediately and gets thrown off a cliff by his father, who claims that his son is weak and would have to survive and climb back up if he was to be his true son as well as his successor. Kazuya barely survives the fall, but is able to climb back up the cliff due to his Devil Gene activating and causing his devil powers to awaken. In the non-canon Tekken: The Motion Picture, this was explained as Kazuya, on the brink of death, making a deal with with the Devil in order to survive to solely murder his father. In the NTSC-U/C (North American) manual of Tekken 2, it was also said that "there is a rumor that Kazuya has made a deal with the Devil," but in canon sources this has never been directly said to have happened. It seems that as the series has progressed, the canon explanation for his devil powers has instead become that his near-death experience simply caused his latent powers granted to him by the Devil Gene to activate. It is revealed that Kazuya was born with devil's power through his mother.

After climbing back up the cliff, Kazuya was raised by Heihachi. This is evidenced by Kazuya's profile in the first Tekken, which states that, since his father is a rich businessman, he doesn't need to worry about money, which seems to suggest that Kazuya remained a part of Heihachi's household. It is also stated that Kazuya and his adoptive brother Lee Chaolan were raised from childhood as rivals, and that Heihachi adopted Lee because he was a skilled scrapper living on his own in the street, meaning Lee would have to be older than 4 years old when he was adopted. This means Kazuya was raised by Heihachi even after he was thrown off the cliff, since he and Lee were raised together. Before the events of the first King of Iron Fist Tournament, Kazuya participated in martial arts tournaments or unofficial fights around the world. In one of these fights, Paul Phoenix fought him to a draw. When the first King of Iron Fist Tournament was announced, the 26 year old Kazuya took the opportunity to get back at his father, setting the stage for the first game.

Personality
Kazuya is driven by his need for control, power, and revenge against his father. After initially appearing to be a sympathetic protagonist in Tekken 1, from Tekken 2 onwards he has shown that everything comes second to his plans for complete control and power. There are very few individuals that Kazuya is not cold or cruel towards. He often laughs at others' misfortune, talks down to them, and in the course of his quest for complete domination, has amassed a large number of enemies, many of whom have been personally injured by his exploits. A notable exception to this concerns Jun Kazama. It is unknown exactly what Kazuya's relationship with her was, but meeting her troubled him enough that he lost concentration in his fight with Heihachi, and ultimately lost everything to him in Tekken 2. Jun believed that there was goodness in Kazuya, and that he could be saved from the devil inside him. The entity Angel is a testament to there being some truth to Jun's beliefs. After he merges with his devil in Tekken 4 however, Kazuya's emotions and desires seem to be more in line with that of his devil. Despite this, Kazuya does initially shows respect and affection towards his grandfather in Tekken 5, and in Tekken 7 continues to harbour anger towards Heihachi for killing his mother, whom he loved dearly.

Unlike his father or adopted brother, Kazuya does not like the limelight. His desire for power seems to stem from an obsession with control and he has little interest in fame. When Kazuya takes over the Mishima Zaibatsu in Tekken 2, he "disappears into the shadows", and likewise, both as an experiment, and later as CEO of G Corporation, he prefers control from the shadows, rather than making public appearances and announcements. This is likely related to his devil form, which he has striven to keep secret from the public.

Despite having a demonstrably cruel streak to him, Kazuya also seems to have a sense of personal honor. He is insulted by Heihachi's accusation in Tekken 5 that he would order JACKs to kill him, calling such a method crude. This is in keeping with Kazuya's overall approach in the games, where, despite at numerous times having the advantage of corporate backing, his personal fued with Heihachi is always confined to tournaments and fights with his own bare hands. This is noticeably different from Heihachi, who has used a gun, abduction, and blackmail during the course the Iron Fist Tournaments, and attempted to kill Kazuya with a laser satellite whilst he was engaged in fighting Akuma.

Kazuya, unlike his devil, Devil mocks Heihachi's attempt to analyse and replicate the power of the Devil Gene through science, in Kazuya's Tekken 4 ending. Kazuya is invested in using scientific study and advancement. He has a personal stake in understanding his own genetics, and has the patience and long term planning to see research as a necessary step on his path to control and revenge. He spends the better part of twenty-one years allowing himself to be experimented on by G Corporation in order to better understand his Devil Gene. It is also noticeable that Kazuya is one of the first ones to work out that Jinpachi Mishima is the sponsor of the 5th Iron fist Tournament. His cool-headedness is also apparent when he temporarily sets aside his vendetta against G Corporation, who have just betrayed him, in order to reason through who is behind the 5th tournament. He has a cunning streak and, much like his brother and father, is capable of being devious and scheming.