Shackled realm
The Adventurers Guild called A-rank and S-rank the liquefying and solidifying realms, respectively. Then they divided the realm above into three ranks.
The SS-rank, SSS-rank, and the Hero-rank.
These three ranks were also called the "shackled realms." When people managed to completely solidify the mana in their mana pool, they would feel the shackles in their bodies—the shackles that were binding their mortal bodies.
It was the limitations of the mortals that were preventing them from reaching godhood. There were ten shackles in a mortal's body, and upon breaking one of these shackles, a person would reach the so-called SS-rank. Then, if they broke four shackles, they would become SSS-rank. And breaking seven shackles will make them reach the Hero-rank.
The Hero-rank was the closest to godhood, yet achieving it was entirely different. The peak of the Hero-rank was completely breaking all the ten shackles inside a mortal's body.