There were tens of millions of tombs buried in the Dao tomb.
These were the graves of true Lord Dao Slayer.
As a Dao-severing expert, he had a long lifespan, but he could not live forever. When the five decays of heaven and man descended, he could only turn into a pile of yellow soil.
When they were old and their lifespans were about to run out, many people would choose to enter the Dao tomb and build a tomb for themselves. Then, they would cut off their own comprehensions of the Dao and turn them into a wisp of Dao soul to benefit the future generations.
The so-called Dao soul was a very strange thing. It contained the memories of a cultivator who had severed his Dao and his comprehension of Dao.
Those who accepted Dao hun later on could quickly comprehend this Dao through their memories and insights.
To put it bluntly, this was equivalent to enlightenment, which made it much easier to comprehend the great Dao.
