The man and his squadron found Ray Palmer, a foreigner clad in mysterious armor, in the woods. The man questioned what kind of samurai Ray was and his intentions. After swallowing an ingestible translator, Ray explained he was looking for a "metal" friend of his who was also in the area. Suspicious, the man had Ray knocked out and brought to Shogun Tokugawa Iemitsu, who desired control of the intruder's armor. In the Shogun's castle, the head samurai tortured Ray on the Shogun's behalf for the secrets of his armor.
Searching for the second "gaijin", the man paid a visit to the Shogun bride-to-be, Masako Yamashiro, to inquire about any foreigners spotted in the area, warning Masako that her future husband didn't want any "surprises" before his wedding. Suddenly, Nate Heywood revealed himself and openly insulted the Shogun. Amused at the "gaijin"'s hubris, the man swiftly beat Nate down before stabbing him in the stomach with a katana. The man and his squadron then left Nate to die, while informing Masako he would bring her to the Shogun tomorrow.
That night, the man confronted Sara Lance, Amaya Jiwe, and Mick Rory, as they burst into the Shogun's castle to rescue Ray. Boasting of his achievements in the war and combat, the man dueled Sara in a sword fight until Amaya knocked him aside, allowing the group to escaped.
The next morning, the man arrived at Masako's village with the Shogun, only to find it evacuated. As the man searched for the villagers, he came upon Sara. Upon realizing she had no master, the man ordered his squadron to kill the "ronin", but Sara defeated them. Mildly impressed, the man proclaimed Sara had fought and would now die with honor, but Amaya and Mick stepped in. After the entire squad was killed, the man rushed at Sara with his sword, but the latter stabbed him in the back with a dagger, killing him.
- "You are already defeated before you have even begun. I have been trained in the art of war by Shimura himself."
- —Head Samurai[src]
- Peak of human physical condition: As the leader of Tokugawa Iemitsu's samurai squad, the man was in top physical condition. He withstood a kick to his ribs from Sara Lance without flinching and could knock her back several steps with a single punch to the face.
- Master hand-to-hand combatant/Martial artist: The head samurai was a highly combatant and martial artist, able to contend with Sara.
- Master swordsman: As an elite samurai, the man was an extremely skilled swordsman, allowing him to duel on par with Sara - who was trained by the League of Assassins - with a single sword while Sara wielded two. The man even pinned Sara down, to the point that Amaya Jiwe had to intervene and knock him down with the Anansi Totem.