Weapon Master — the stage at which the Giant's path stops being only about fists. The strength, constitution, and agility of the bearer are already superhuman, but the main skill lies nearby: everything that can be taken in hand as a weapon obeys him at a master's level.
This is not about a habit of the blade or a rifle. The moment an object ends up in the hands of the Weapon Master, he wields it as if he had studied it for years — including things a normal person would not risk using at all:
otherworldly blades and firearms;
mystical objects;
sealed artifacts in the form of weapons.
Moreover, the harm from the side effects of such things is noticeably weaker for him: an artifact that would drive a random owner insane remains manageable in the hands of the Weapon Master — up to a certain limit.
Hence the method of action of the stage: the more dangerous the thing the bearer subjugates, the faster his mastery grows. Here, for the first time, the Giant's path rewards not caution but calculated risk.