Jin Sakai (bolrn 1247) was a Japanese samurai, Rōnin, and rebel who fought against the first Mongol invasion of Japan in Tsushima, which was led by Khotun Khan. Though initially suffering from defeat at Komoda Beach and Castle Kaneda, Jin eventually gained valuable allies and skills which enabled him to capture significant portions of the island, becoming known as the Ghost of Tsushima. At the cost of this, however, was Jin's adherence to bushido: the samurai code; this damaged his relationship with his uncle Lord Shimura. Jin was captured by Kamakura Shogunate forces after poisoning the Mongols at Castle Shimura, eventually escaping and being exiled by both his uncle and the Shogun Prince Koreyasu.
Jin managed to gather his remaining allies and also contact Lord Shimura for an assault on the Mongol stronghold of Port Izumi, where Khotun planned on taking off towards Honshu to use Jin's poison against the Shogunate. He eventually confronted the Khan on the battlefield, beheading him after a lengthy battle. In the aftermath, Jin and Shimura met at the Sakai family home in Kubara, where they discussed various topics before Shimura revealed that he was sent to kill Jin as a traitor to the samurai and the Shogunate, having inspired rebellion in the wake of the samurai failure and significant support of the Ghost.
Tearfully, they wrote death poems for each other at Kazumasa Sakai's grave, before commencing in a duel to the death. Jin gained the upper hand, Shimura surrendering and begging Jin to take his life. He spared Shimura, fully embracing his role as the Ghost and leaving bushido behind. In the aftermath, Jin finished off the last of the remaining Mongols on the island, eventually leaving for Iki Island to end the threat of Ankhsar Khatun and the Mongol Eagle Tribe.