Name: Five Emperor True Manual (Saint Rank cultivation method)
Level: 10/24 (as of Ch-1275)
Each level of this method is equal to a stage of a realm (ex : level 5 is equal to 5th grade acquired level, level 10 is equal to 1st stage innate level and level 19 is supposly equal to 1st stage celestial level).
Foreseeably, the difficulty of cultivating this true manual would get greater and greater as one progressed. Upgrades through layers would in units of years.
After reaching a bottleneck, unless one achieved a suitable level of comprehension, they could get stuck for several years.
For example, to proceed from the 9th layer to the 10th layer, Ouyang Shuo had used nine months. For context, he also took nine months for the first eight layers.