The descent took three attempts to get right.
The relay technique required deploying shadow soldiers as fixed anchor points through successively deeper Underworld layers, then using the connected thread of void-substance between them to maintain his mortal anchor while his consciousness and body traveled deeper than the First Layer.
First attempt: he deployed twelve shadows as a relay chain into the First Layer and tried to push the chain further down. The connection broke at the boundary between layers one and two. The shadows had insufficient void-density to hold the link at layer transition points.
Second attempt: he replaced the relay chain with his highest void-density soldiers. The Einherjar, the Myth-Born Echoes, Herald at the deepest point. The chain held through the First Layer and halfway into the Second before Herald's cognitive disruption created interference.
Third attempt: he put Nyx at the deepest anchor point, with Stormward as the Second Layer relay, and went himself.
The transit through the Second Layer was fast. A blur of dark-sky space occupied by enormous shadow-beings that noticed him and chose not to engage. Their attention tracked his passage the way very large predators track things that move through their territory with sufficient confidence to imply they belong there.
The Third Layer arrived as a city.
He had not expected a city. The mythological traditions he had studied described the accumulated neutral dead's domain as a plain, an expanse. But traditions simplified. The reality was a city that had been built over uncountable time by the accumulated contributions of every culture that had ever died and not belonged specifically enough to any single pantheon to be claimed by a mythology's specific afterlife domain. Babylonian ziggurat beside Norse longhouse beside Aztec pyramid beside Greek agora beside buildings he had no cultural framework to identify at all.
Its scale was geological. He could not see the edges.
His Void Sight showed him the aura composition. White. These were the dead, not the Underworld's native creatures, and in their death-state their soul-substance had a different quality from the living. Not extractable. The system specifically did not flag them for Shadow Extraction, a distinction he noted with some relief. But present, aware, watching him with the patient curiosity of beings who had long since stopped having anywhere to be.
Liu Yun walked through the city's outer districts for twenty minutes following the Void Sight's compass-sense toward the contact the Oracle had identified. The dead who saw him reacted with consistent recognition. Not of him specifically, but of what he was. The Void Sovereign title's passive effect was operating, the involuntary threat-response, but in the dead it manifested differently than in the living. Not fear but deference. They stepped aside. They bowed their heads.
The contact was in a structure at the city's center that was larger than the other buildings not through height but through depth. It seemed to extend downward into the Third Layer's substrate rather than upward, an inverted tower. Its entrance was guarded by two entities that were not the neutral dead.
They were shadows.
Very old shadows. Not his. Not from his Register. But the same substance, the same violet-tinged darkness, bearing the unmistakable imprint of Void-type origin. They looked at him and their eye-lights recognized him immediately.
'The new Sovereign,' one of them said.
'Tell your master I'm here,' Liu Yun said.
The entity inside the inverted tower was a woman. Or she wore a woman's form with the same comfort that the Oracle wore an old woman's form. The most functionally appropriate vessel, not necessarily the accurate one.
She was dark-skinned and grey-eyed and she wore the clothing of a dozen different mythological periods layered on each other. The oldest garments at the bottom, visible at the hem and cuffs and collar beneath the more recent additions. She looked at him across a table covered in objects that were clearly from different cultures and different centuries and said:
'You look like him. More than most.'
'You knew the first Void Sovereign,' Liu Yun said.
'I was his strategist. In the mortal world I was a warrior and a seer. In death I came here and stayed because the Seventh Layer's expansion is old business and I am not done with it.' She gestured to a seat across from her. 'Sit. We have a great deal to discuss.'
Her name, she said, was Mira. She had been the first Void Sovereign's battle commander, not a shadow soldier but a living companion. The woman who had stood beside the original Liu Yun, not inside his Register but at his shoulder, doing what Sera now did. When the first Sovereign died in the stopping, she had died alongside him. She had been in the Third Layer for four thousand years.
'He died because Bael's fundamental vulnerability was not identified in time,' Mira said. 'The first Sovereign reached the Seventh Layer with sufficient power to damage Bael severely. But damage without eliminating the vulnerability is temporary. Bael regenerates, rebuilds, and sends the next Avatar against the next iteration.'
'What's the vulnerability?' Liu Yun asked.
Mira looked at him steadily.
'His name,' she said.
He waited.
'Every Demon King of the primordial classification has a true name. The original designation given at their creation, before they chose their identity. The true name is the fundamental structure of their existence. It cannot be spoken in the mortal world. The dimensional resonance required to activate it only exists in the Seventh Layer itself, in the chamber at the center of Bael's court.' She paused. 'The first Sovereign reached that chamber. He did not know the name.'
'And you do?'
'I learned it in four thousand years of research in the Third Layer's archive.' She held his gaze. 'I will give it to you. But Liu Yun, you need to understand. Speaking the true name in Bael's presence will shatter his current form completely and permanently. It will not merely defeat him. It will unmake him.'
'Is that a problem?'
Mira was quiet for a moment.
'No,' she said. 'It is justice. But it will also draw the attention of every divine and demonic power in the Underworld, because unmaking a Demon King changes the layer hierarchy in ways that nothing has changed it in millennia. You need to be prepared for consequences that extend beyond Bael.'
'I'll manage the consequences,' Liu Yun said.
Mira studied him.
'Yes,' she said, slowly. 'I think you probably will.'
She taught him for three days. The layout of the Seventh Layer, Bael's court structure, the six guardians that stood between the layer entry point and the central chamber, the specific void-frequencies required to navigate the Seventh Layer's hostile mana environment without burning through his reserves at unsustainable rates.
And on the last day, in a voice that was precise and careful and four thousand years old, she gave him the true name.
He held it in his memory like a held breath.
Then he followed the relay chain back up through the layers and came through his Portal into the Ash Ridge forest in the grey morning light of the surface world.
He was ready.