Duncan had read extensively on how a cultivator progresses in Sword Dao, due to his interest in it.
Especially after he had performed the sword light consciously for the first time, Duncan had tried to read as much as possible on the various stages of sword cultivation.
A sword cultivator can be differentiated in strength based on the stage at which his Sword Dao has progressed to. There are basically five stages of Sword Dao that are known to cultivators in this world.
The first stage is the Sword Light.
This is the stage Duncan was at. Duncan had already achieved this state due to his innate talent even before entering the Grotto Heaven. However, only during the fight with the Wang Clan Patriarch did he truly grasp and began controlling. The true mark of control for a cultivator is to manipulate the sword light in whichever way they saw fit.
