Part I: A Lady so Blessed and Beautiful
Yuriko Oyama is the daughter of Kenji Oyama, a brilliant inventor who flew for the Japanese military during World War II. A kamikaze pilot, it was Kenji’s duty to crash a plane loaded with explosives into a military target and die in the ensuing explosion. Kenji valued his honor as a warrior above all and fully intended to complete his mission. However, when he crashed his plane into his mark, a U.S. aircraft carrier, the bombs on his plane didn’t explode—a freak, one-in-a-million occurrence. Oyama, to his dishonor, survived the crash. It left his face horribly scarred, but otherwise, he was fine. [Daredevil (1st series) #197-199, Wolverine (2nd series) #37]
The Americans took Kenji as a prisoner of war, and released him to the Japanese after the war ended. He wrote a book about his experiences, made a lot of money and bought a private island off the coast of Japan, proclaiming himself Lord Dark Wind. To hide his scarred face, Dark Wind donned a permanent shroud over his head. To Oyama, the shame of failing in his mission was a fate worse than death. He devoted his life to redeeming himself, which he intended to accomplish by restoring Japan’s honor. An isolationist, Lord Dark Wind considered Japan’s foray into free trade and Westernization a perversion of the great nation’s honor, and planned to revert Japan to the noble way of the samurai. Using his metallurgy skills, he began developing a process whereby regular men could be transformed into indestructible superhumans, a process he would then sell to the Japanese military for them to use to elevate their military force. [Daredevil (1st series) #197-199]
During his period of exile, Lord Dark Wind also fathered three children: a daughter named Yuriko and two sons. He also became acquainted with an American religious figure, Reverend William Stryker. Despite their vast cultural differences, the two somehow became friends, and the Reverend’s wife even became the personal tutor for Kenji’s daughter Yuriko while they were in Japan. Yuriko grew fond of both the Reverend and his wife, and stayed in touch with them over the years. [X-Treme X-Men (1st series) #25-26]
When his children grew up, Lord Dark Wind branded their faces with a Japanese symbol whose meaning was known only to him. He amassed a devoted following of people who fervently believed in his nationalistic ideas, including his two sons—both of whom reportedly died serving him. Yuriko, however, shared neither their ideals nor their fate. She grew to hate her father for his fanaticism and for his backward beliefs. In addition to losing her brothers to his vendetta, her lover Kira became enamored with Dark Wind’s ideals as well, much to her dismay. After Kira was recruited into Dark Wind’s samurai cult, Yuriko devoted herself to breaking him free from her father’s spell.
Meanwhile, Lord Dark Wind continued making great strides with his metal-bonding research. He decided that the elusive metal known as Adamantium, which was in its early developmental stages, would work best for the proposed process of being bonded to human bones. However, his research was stolen by Weapon X, who then used it to create its own super-soldiers. Dark Wind managed to recompile all of his research and equipment after it was stolen. Unfortunately for him, he only got to perform his Adamantium-bonding process once, on an American super-villain Bullseye, who came to him with a broken spine.
Around this time, Yuriko was captured by her father and jailed on a freight ship when he learned she was working to undermine his goals. She aboard this ship when the American superhero Daredevil sneaked aboard in search of Bullseye, his nemesis. When he found her in captivity, Daredevil freed Yuriko, and, together, they escaped. 
Yuriko revealed to Daredevil some fragments about Dark Wind’s history, but concealed her connection to him. She only stated that she wanted to free her lover Kira from his spell. When Daredevil asked Yuriko why she always hid the left side of her face, which bore her father’s brand, she tearfully revealed what her father had done to her. To her surprise, however, Daredevil didn’t find the scar unattractive (unbeknownst to Yuriko, the man was blind). The two of them grew close during the course of their journey together, and possibly even made love the night before they stormed Lord Dark Wind’s fortress. [Daredevil (1st series) #197-198]
The next day, amidst a freak series of earthquakes, they stormed Dark Wind’s palace together, and Daredevil fought his way through Oyama’s men. However, a chance tremor caused part of the mansion to collapse on Daredevil, and he found himself at the mercy of Lord Dark Wind. To his surprise, Yuriko sneaked up behind her father and stabbed him in the back, slaying him for his unworthy ideals. Afterward, she reunited with Kira, who worried he had failed his master, and the two lovers left together. [Daredevil (1st series) #199]
Presumably, Yuriko never spoke with Daredevil again. All was not well with Kira, however. With his master dead, Kira couldn’t go on living, and committed seppuku, plunging his sword through his torso despite his lover's tormented objections. The devastated Yuriko quickly learned that her father's death would not grant her the release she craved; she would not be able merely to flee the shadow cast by his memory. To cope, she began investigating her father’s legacy once more. For some reason—perhaps the trauma of having slain the man herself, or from seeing how deeply his philosophy affected the man she loved—Yuriko found herself, for the first time, embracing her father’s beliefs. She grew obsessed with restoring his honor and redeeming herself and her family name. She decided to carry out his legacy by using his Adamantium-bonding research to build an army of super-soldiers for Japan with the intention of restoring the great nation to its former glory—her father’s original goal. In the meantime, she vowed to get revenge on those she believed had stolen her father’s research. [Alpha Flight (1st series) #34]
One of her first targets was the shapeshifting mutant mercenary Mystique, along with her adopted daughter Rogue, their accomplice Sunfire, and their associate, Blindspot, a mutant with the ability to remove people’s memories. Mystique’s crew, it seemed, had raided one of Lord Dark Wind’s laboratories in an attempt to steal the secrets of the Adamantium-bonding procedure, and had torched the laboratory in the process. Yuriko somehow got it in her head that they had successfully stolen the Adamantium research, however, and decided to smoke them out. What Yuriko didn’t know was that they had failed, and that their associate, Blindspot, had severed ties with the group and erased their memories of her existence. When rumors of Oyama’s vendetta reached America, Blindspot, in an effort to protect her old cohorts from Dark Wind’s wrath, traveled to his home. She discovered that Yuriko had replaced her father, and erased her memory of the incident as well. Although Rogue, Mystique, Sunfire and Yuriko all forgot this incident had ever occurred, it would have lasting repercussions for them later in their lives. [Rogue (3rd series) #10-11]