The grotto-heavens in the Two Heavens generally possessed vast quantities of Dao marks.
The primary source of these Dao marks was not tribulation passage, but the contributions of generations of Gu Immortals.
For example, Soothe Soul Grotto-Heaven possessed over seven million Dao marks! Such an abundance of Soul Dao marks had resulted in a great number of super resource points within the grotto-heaven.
The original Soothe Soul Grotto-Heaven had only a little over a hundred thousand Soul Dao marks. After it annexed a large fragment of the Nine Heavens, it had been free from disasters and tribulations ever since.
Supported and cared for by heaven's will, Soothe Soul Grotto-Heaven produced Gu Immortals generation after generation.
These Gu Immortals were all human. Although they could freely choose their cultivation paths, the overwhelming majority chose Soul Dao.
This was because the grotto-heaven's Soul Dao resources came in every variety and were abundantly stocked, truly blessed by heaven and favored by earth. Even among Gu Immortals who chose other paths, their numbers were exceedingly few; obtaining cultivation resources for other paths was far more difficult for them than obtaining Soul Dao resources.
In fact, the Primeval Two Heavens were not places that ordinary rank 6 and Rank 7 Gu Immortals could enter and explore.
Generally speaking, only a small number of powerful Rank 7s, along with ordinary Rank 8s, could explore the Primeval Two Heavens, braving danger to gather a certain quantity of wild resources.
After these Soul Dao Gu Immortals died, their immortal apertures were almost all merged into Soothe Soul Grotto-Heaven.
Although these Gu Immortals did not possess the Supreme Immortal Aperture, and merging apertures caused considerable internal losses, the mainstream Dao marks had always been Soul Dao marks. Thus, for most periods, the gains from merging exceeded the losses.
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