Knives
The art of wielding a knife, or tantojutsu, is not typically considered a priority at most bushi dojo. The katana is the principle weapon of the samurai, of course, and even if one chooses to take up another weapon instead, there are many more effective, more lethal weapons than a simple knife. Yet despite this, virtually every bushi in the Empire is trained in the use of the knife, and carries on at all times. Bushi are imminently practical warriors, after all.