Ryo Sakazaki/Story

Past
Ryo is the son of Takuma Sakazaki and Ronnet Sakazaki and the older brother of Yuri Sakazaki. Born in the city of Southtown, as Ryo was deemed to be Takuma's successor, he began his martial arts training at an early age. His father instilled him with the difficult principle of self-reliance, where a person's own strength can form their worth in the world, but these days of his childhood training would prove difficult for the young Ryo, who was reluctant to fight due to his kindness and bashfulness. He eventually gained a sparring partner and friend when Robert Garcia was admitted into the dojo.

On Ryo's 10th birthday, his mother died in a tragic car accident. Immediately after, his father mysteriously left their home and left Ryo to take care of Yuri. Forced to fend for himself and his sister's sake, Ryo did this by partaking in construction work and tirelessly strived to defend his family's dojo. Remembering his father's lessons during his training, he also took up street fighting. At first, he did poorly but, after many years of persistence and learning the true meanings behind his father's teachings, including "A man's strength cannot be known only by his fist", "Real strength must be felt through the mind and heart", and to know what he was fighting for, he eventually established himself as a fearsome and renowned street fighter.

Art of Fighting
In the first Art of Fighting, Yuri is kidnapped by Mr. Big, a local criminal mastermind of the dangerous city, South Town on behalf of Geese Howard. During his journey, Ryo met a bouncer named King, who guides them to Mr. Big's location. With Robert and King's help, Ryo confronts and defeats the kingpin. His pursuit for Mr. Big leads him to a karate dojo where a mysterious man challenges him. When Ryo prevailed, he threatens to finish Mr. Karate unless he told them information about Yuri's safety. Before he deals the final blow, Yuri reveals the man's identity as their father. After eleven years of separation, the whole family is reunited.

Art of Fighting 2
Before the events of the game, Ryo went to the mountains for training. He received an invite for a King of Fighters tournament and accepted it to test his strength. When he reaches the finals, the tournament's host, Geese Howard, expresses his desires to recruit Ryo into his services. Ryo refuses and subsequently fight him atop his office in Geese Tower, and defeats him with tremendous effort. Unfortunately, Geese manages to escape and later enacts the beginning of the Fatal Fury story.

Art of Fighting 3
Ryo's role in the following game is reduced to being a supporting character for Robert. In his ending for the game, he hands his sister a ticket for Robert's flight back home and wishes the best for both of them. Additionally, he gains two new rivals: Kasumi Todoh and Jin Fu-Ha.

Fatal Fury series
Presumably, after the Art of Fighting series ended, Takuma retired from fighting and entrusts the Kyokugenryu dojos to Ryo. At least two dojos are in operation, one near Southtown and one is later entrusted to Ryo's student, Marco Rodriguez. This is supported by the fact that Ryo takes over the Mr. Karate mantle that his father once held in Fatal Fury: Wild Ambition and Buriki One.

The King of Fighters series
Ryo's life is the exact same as his Art of Fighting/Fatal Fury counterpart up until Art of Fighting 2.

Throughout the series, the Kyokugen style is depicted as a struggling family business, funded almost entirely by prize money earned from KOF and Robert's vast wealth. Each year, at the conclusion of KOF, the Kyokugen dojo would often have many applicants due to the strong performance of the team. Despite their hard fought success, most of these applicants would later quit, due to either the strenuous training regime or mysterious people who appear and trash the dojo. The family manages to keep two gyms running, one in South Town and a second in Mexico. Ryo usually teams up with Robert, Yuri, or Takuma to continue spreading the fame of the Kyokugen style. He usually tries his best to keep his sister away from the tournaments and relents to his father's demands. In The King of Fighters XI, Ryo indicates that Marco is currently a green belt.

The King of Fighters '94
Prior to the 1994 tournament, Ryo learns that Yuri entered KOF on her own accord, despite being told it was too dangerous. Takuma Sakazaki tells him and his friend Robert Garcia that they should enter KOF to put their training to the test as the Art of Fighting Team, representing Mexico.

The King of Fighters '95
Takuma forces Ryo and Robert to participate in KOF '95, wheater they like it or not, forming the Kyokugenryu Team again.

The King of Fighters '96
Takuma talks to Ryo, Robert and Yuri about this upcoming KOF tournament. He announces that he'll be retiring starting this year, and requests that Yuri should team up with Ryo and Robert, much to the former's disdain. The three team up as the new Kyokugenryu Team.

The King of Fighters '97
Prior to the 1997 tournament, Takuma is injured by an unknown attacker. Ryo, Robert, and Yuri once again team up to form the Art of Fighting Team, to discover who injured Takuma prior to the tournament.

The King of Fighters '99
Ryo, Robert and Yuri form the Art of Fighting Team, with Takuma joining them, now fully recovered.

The King of Fighters 2000
In The King of Fighters 2000, Ryo welcomed King into the team, even through Robert's protests, as Yuri back to the Women Fighters Team. Takuma apparently noticed (and mistook) the respect the young fighters had for one another for love and presses his wishes for her to join whenever the time calls for it (something Robert and Yuri would eventually do too).

The King of Fighters 2001
To be added...

The King of Fighters 2003
To be added...

The King of Fighters XI
To be added...

The King of Fighters XIII
To be added...

The King of Fighters XIV
By the time of The King of Fighters XIV, the Sakazaki family has opened a Kyokugen BBQ restaurant with the help of Richard Meyer. Ryo, displeasing with his family attitude regarding their training, is determined to leave South Town and is accompanied by his student, Khushnood Butt.

The King of Fighters XV
King leaves the Women Fighters Team, and replaces Yuri in the Art of Fighting Team, not only due to her allowing Athena Asamiya to lead the team in her stead. Ryo's impatience with the family's complacency with the restaurant pushes him to the limit and causes a rift between his younger sister Yuri. Confiding to King about his frustrations, he then dons the Mr. Karate mask and "transforming" into Mr. Karate II, then demands that everyone rekindle their resolve for the martial arts to be stronger and ends up leaving the business in Marco's hands, as everyone in the family undergoes retraining in the mountains.