Stepping into the Nebula-Grade Realm was not a big deal for Luo Yunyang. He believed that he was already up to that standard and could break through to the Nebula-Grade if he wished to.
However, breaking through to the Nebula-Grade would be a great leap for him. He hadn't done so because he thought that there were some deficiencies in his Origin Source Law, especially in the Great Chaotic Hole Path.
Despite receiving plenty of assistance from the mystic techniques created by the geniuses, Luo Yunyang faintly felt that there was a flaw in his Great Chaotic Hole Path while his cultivation increased. It was actually a big flaw.
Although this flaw could be ignored, Luo Yunyang somehow felt that there would be a huge impact on his cultivation if he chose to ignore it and proceed.
Based on his evaluation, the best solution would be to browse through all nine sets of Sky Books.