Athan's training for everyone to endure pain proved to be extremely useful because the path of body order ken in Zen realm and further is very tough and painful.
So everyone made rapid progress, and after three years, all of them reached the 3rd stage of the Atmospheric Body Realm, which is called, Physical Body Armament Manifestation.
Athan had reached the 3rd stage in just one year because he was already at the peak of the 1st stage of the Atmospheric Body realm, Physical Body Force Manifestation, and he progressed faster than others.
However, he had to stop after reaching the peak of the Atmospheric Body realm because he needed to ascend to the upper-chaosverse to break through to the next body realm.
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