Tyler could feel the yin-yang energy entering his body. It was moving into his mana space, where a large amount of mana was being produced.
The yin-yang mana was filling up the mana space, but his mana space was massive. Without something like the Great Dao Technique, it would take some time to fill it.
More importantly, he was also gathering the blood energy and soul energy. While training his spear techniques, Tyler had fully recovered his soul energy.
So, he used his yin-yang energy to refine more soul energy and blood energy while also refining mana.
The size of the Inner World was based on how much of those things could be produced and merged.
The Foundation Establishment Realm was about creating a pool that could store mana, training the body to bear the weight of the mana, and tempering the soul.
The Golden Core/Inner World Formation Realm was about merging the mana stored within the mana space, blood energy, and soul energy.
