The Mongol Empire is invading our home. They are brutal, relentless, unstoppable. We are eighty samurai... against an army. Fighting to slow the invasion. Today, I die for my people.
― Jin Sakai in Prologue
The Battle of Komoda Beach was a battle between the Samurai and the Mongol soldiers, during the initial stages of the Mongol invasion, at Komoda Beach. The samurai forces under Lord Shimura suffered a decisive defeat against the Mongols under Khotun Khan, resulting in the nigh-extinction of Tsushima's samurai.
Battle[]
Honor died on the beach. The Khan deserves to suffer.
― Jin Sakai to Lord Shimura in The Fate of Tsushima
As the Mongols began to gather on the beach, Lord Shimura sent his greatest warrior, Lord Harunobu Adachi, to challenge the greatest fighter, in an attempt to prevent a large-scale battle. Approaching the Mongols on their beach, Lord Adachi challenges them to send their finest warrior to fight him. The leader of the Mongol forces steps forward and throws oil on Lord Adachi, sets him on fire, then decapitates him; an act that knowingly insults the samurai code of bushido. The Mongol leader then demands the samurai's surrender. Outraged by the invaders' violation, Lord Shimura declared them cowards without honour and commanded a furious charge down the beach.
After unleashing a volley of arrows, the samurai charged against the Mongol army. Lord Shimura and his nephew Jin Sakai led the charge against the Mongols on horseback, cutting down many and pursuing the Mongol leader after he fled. However they are dismounted by naval artillery, with Jin trapped under his fallen horse. Lord Shimura narrowly saves him from an approaching Mongol soldier, then leads him and the few surviving samurai to kill the Mongol leader. They reached another section of the beach and encountered heavy Mongol resistance, where all of the remaining samurai are eventually killed. Lord Shimura and Jin were the last warriors still alive, with the two making a last-ditch effort to finally eliminate the Mongol commander and end the invasion. After travelling past the burning buildings close by, the two spotted the Mongol leader and rushed him, but were knocked down by sudden artillery. Jin recovered and attempted to reach his sword, but was hit twice in the back by arrows and passed out from his injuries.
Captured by the Mongols, Lord Shimura comes face-to-face with the Mongol leader, who reveals himself to be Khotun Khan, cousin of Kublai and grandson of Genghis. The Khan praises Shimura's fighting skills and reveals his preparations for the invasion; studying and learning the Japanese language, culture and valued honour traditions, as well as how to effectively control Tsushima by burning or taming select villages. Khotun again demands the jito's surrender, which Shimura bravely and wordlessly refuses. As it appears the Khan may execute him, he instead knocks the samurai unconscious and takes him captive in his stronghold, Castle Kaneda.
Of the 80 samurai who fought to defend the island, all except Jin and Lord Shimura were killed, including the lords of Clan Adachi, Clan Nagao and Clan Kikuchi, Lord Harunobu Adachi, Lord Hirotsune Nagao and Lord Kikuchi, as well as Lord Adachi's two sons Shigesato and Yasunari, their friends Masanori and Ujikage and all of Clan Nagao, possibly including Yasumasa Sasaki. Jin is later rescued from Komoda Beach by a young thief named Yuna, who nurses him back to health and joins his later efforts in reclaiming Tsushima from the Mongols.
According to Ryuzo, the Straw Hats also suffered half of their forces, including their previous deceased leader, during the Battle of Komoda Beach. The Straw Hats started to slowly suffer in starvation, Mongols, which led some members to cut ties with the group.