Each of the Sinjid games seem completely non-canon to one another, which means that Fujin, despite similar backgrounds in each game, is likely a different person in each.
Sinjid Shadow of the WarriorEdit
Fujin is a young warrior hailing from a small unnamed village. He is close friends with Hattori, considered the guardian of the lands. When their village is overrun by the Fallen Army, Fujin is tasked with taking Hattori's infant son into the mountains and raising him in the ways of the shadow.
Fujin does as asked and trains Sinjid in the safety of the mountains for twenty years. Near the end of Sinjid's training, Fujin tasks Sinjid with going to the Shadow Temple and defeating all the enemies in the human gateway. As Sinjid leaves, Fujin travels to the highest peak of a nearby group of mountains.
When Sinjid returns successful, he finds a note from Fujin, explaining that he has gone to seek a friend near the northern coastline. In the letter, Fujin tasks Sinjid with protecting the highlands, additionally stating that Sinjid is to meet an unknown person at the peak of the mountain.
In Sinjid, Fujin was considered the greatest shinobi in the land. He found Sinjid as an orphan, and raised him with care, training Sinjid to be a powerful Shinobi in his own right. However, at least seven years prior to the game, Fujin died suddenly. Sinjid was falsely charged with his murder, and remained imprisoned until Captain Masaru required Sinjid's services as a warrior.
Sinjid is given a quest in exchange for his freedom: defeating a Shogun who has started an ongoing war. Sinjid however, believes that he can also track down Fujin's true killer. Soon after completing the quest, Sinjid learns of a man named Kazuro, and begins tracking him, feeling a connection to the man.
During their confrontation, Kazuro reveals that Fujin trained him as well; like Sinjid, Kazuro was an orphan that Fujin took in. Kazuro would later kill Fujin, believing that the kindness Fujin gave orphans was suspicious. Kazuro claims that Fujin killed both Kazuro's parents and Sinjid's, as guards often killed parents during times of war. Sinjid, however, refuses to believe this given a lack of proof, choosing to believe that Kazuro had selfish reasons for killing Fujin.