Let's create a scenario, now. The gaijin knight is visiting Japan with a few of his noble friends. They're in a small coastal village, recounting the times they've driven horses into the backs of peasant lines, when the knight bumps into the samurai. The samurai stares him down, expecting him to beg forgiveness, but he doesn't. So the samurai moves to cut him down, but the knight's friends suggest that instead of having this happen here, they both fight an honorable duel toward the nearby hill side.
Both of them having much honor at stake, with the whole village watching, agree. So now we have preparation. Well the Samurai is a practitioner of bushido, but luckily for him, bushido is for when important people are watching, and doesn't even apply to the rude gaijin in a tin can. So the samurai drafts an army of conscripts, hands them pointy sticks and armored rice hats, and then uses his extreme wealth to buy like six hundred war dogs. He gives each war dog a badass little wooden mask, and names them all “Kira-Seiko-So-Ru-Shittah”, or “Kill-Fuck-Soul-Shitter”. The samurai then rides off, gets all his samurai friends, and tells them that they have a guy to kill FOR GREAT HONOR.