Master Forger.

Shi Lang used the hammer to fold the hot metal into itself multiple times. The big pile of metal was reduced to a stick that was three feet tall. The forging masters knew this weapon was a sword but did not know the type. 

To make a spiritual weapon, one had to carve array patterns on the weapon that allowed a smooth flow of the energy inside the weapon. It was like an electric circuit; one wrong line would cause a short circuit. They wanted to see what Shi Lang's limit lay. 

His ability to refine the metal a hundred times impressed them. After all, Shi Lang came from a martial artist background. They had to admire him for that. A hundred refinings did not mean beating the metal with the hammer a hundred times. It meant the forger needed to hit the metal and remove its impurities. All hundred hits were to purify the metal and make it denser.