What Xiao Shi chose was the Domain Dao of inferior-class mortal Dao. The specialty of this Dao was mainly the development and strengthening of the domain. But he did not choose this Dao to develop his domain.
After all, his domain was already far stronger than ordinary domains. There was no need for him to develop it specially through the Domain Dao.
Xiao Shi chose this Dao because he wanted to use the Domain Dao to expand his body's Dao River. He thought that as long as he suppressed his Domain Dao in the Dao Suppression Sword and fused it into the Dao River, he could use the Domain Dao suppressed by the Dao Suppression Sword to expand the Dao River.
The Dao of Domain could not only bring about greater development to one's domain, it also applied to the Dao River. Expanding the Dao River with the Dao of Domain was undoubtedly smoother and easier than Xiao Shi developing the Dao River himself.
