After exhausting the faith energy from the octagonal crystal, it was much easier for Hiro to take the treasure into his system's inventory.
It only cost him 10,000 achievement points.
While Hiro was surprised by the low price, the system told him that this mirror was only a fragment of a greater treasure, hence the low price.
As it turned out, there was a hard limit on the number of "prisoners" this mirror could contain at a time, not to mention their individual and collective strength.
Yes, there was a limit on the individual strength of a captive and the collective strength of all captives inside the illusory world.
When the Mirror World entered the system's inventory, Hiro's consciousness returned to his body automatically. Furthermore, the consciousness of the millions of demons trapped inside were also released into the world.
