Street Fighter II/Ryu

Ryu was an orphaned child, with no knowledge of who his parents were or if they are still alive. When Ryu was a young child, he was adopted by a man named Gouken and began living with him as well as learning the mysterious and dangerous martial art known as Nin-Ansatsuken. Gouken would later train his best friend's bratty son, Ken Masters, who served not only as a sparring partner for Ryu, but also to give Ryu some company since Gouken was the only person Ryu had seen in a long time due to the seclusion of Gouken's dojo. Ryu looked up to Gouken as a father figure during his early years and Ken as a best friend and surrogate brother, which is how their relationship remains to this day.

When Ryu was about 23 years old, Gouken thought that Ryu was ready to travel the world in order to test his skills against the best fighters in the world. With this, Ryu left Gouken and Ken, and headed to fight in the first World Warrior tournament. After defeating all challengers, his skills earn him the right to fight its host, Sagat. Despite nearly losing against the "Emperor of Muay Thai," Ryu secures a difficult victory, and is crowned champion. Years later, after the events depicted in the Street Fighter Alpha series, Ryu enters the second World Warrior tournament to test his skills.

Fighting Style
Both Ryu and Ken are practitioners of an extremely violent martial art known as ansatsuken (Japanese: 暗殺拳 murderous/assassin's fist), which incorporated the most violent techniques from a blend of four styles of martial arts, alongside a mysterious sure-killing technique called Shun Goku Satsu. Both Ryu and Ken learned their art from Gouken, who vowed to teach a less violent variation of the art created by his master Goutetsu which does not include the discipline's life-threatening techniques such as the Shun Goku Satsu.

While Ryu and Ken follow the same martial arts discipline, as the Street Fighter series evolved, the differences between the two characters was portrayed by their attacks: Ryu focused on technique while Ken opted for stylish unpredictability.

Ryu's normal attacks are slightly slower than Ken's, albeit straightforward. His special moves are more focused; Ryu inflicts damage with individual strikes rather than combinations. His Shoryuken does only one hit, so Ryu can effectively use this move at full power against airborne opponents, although Ken's is still much stronger since he follows the Shoryuu principle. Ryu can dodge projectiles at the start of his Tatsumaki Senpuu Kyaku maneuver and knocks an opponent down with one hit.

Ryu focuses more on the Hadou principle of Goutetsu-style Ansatsuken, which translates to him being very skilled with his usage of ki - Ryu has the most concentrated Hadouken amongst all "non-lethal" Goutetsu-style Asatsuken users, and only the "lethal style" Goutetsu-style Ansatsuken user, Akuma, can match and/or surpass Ryu's Hadouken in both gauge and concentrate in certain instances. Ryu is the only student of Gouken's style of Goutetsu-style Ansatsuken capable of using the Shakunetsu Hadouken with the greatest of care—ensuring that the surge still burns bright with flames, but won't result in immolation.