Alen_Tanor

Cultivating his power by slaying demons and taming countless beasts, the emperor solidified his throne as the world's ruler. But not once in his life had he expected that his disciples would use research on demonology to sap the world tree's power and push the world to destruction.
Trying to fix his mistake, he opted to use all of his cultivated power to cure the world tree and block anyone from sapping its power ever again. But in exchange, he was to lose all of his power.
But...the worst had happened, his wife... had betrayed him.

Legends: The Emerald World

"The heaven-piercing homunculus prison? That tower is still standing?" Arachne gasped, that tower was built by Shin to house the most vile of criminals and keep them locked for thousands of years. Technically it's self-sufficient the avoid the cost of keeping prisoners, but it's also nearly inhospitable to life.

[After the end, the air around the prison slowly became toxic and killed all of the prisoners. Gi retreated to it to heal her wounds after the last fight with Shin's wife, but she ended up dying a hundred years afterward.]

"Sofia did wound her core pretty badly, but she's a homunculus, she should've been able to survive," Arachne growled looking at Shin who was listening from the side.

[Sofia's attack caused her more damage than was initially apparent. Her function slowly deteriorated as the only one who knew how to repair her was Shin over there. At the time he was dead so she slowly perished.]

The Heaven-Piercing Homunculus Prison