In the fourth vault, the chamber Frank initially dismissed as a hollow void was actually a masterpiece of deceptive architecture. It was constructed with such precision that unless the exact password and ritualistic passage were followed, the true interior remained phased out of reach. While it appeared vacant to Frank's untrained eye, the space was teeming with activity, occupied by various soul beings and a vast wealth of resources.
The soul beings within were organized into three distinct operational branches:
The Alchemical Unit: Charged with the delicate task of converting exotic flora into raw life energy.
The Logistics Unit: Responsible for categorizing combat gear and household wares crafted from the second vault's specialized textiles.
The Curators: Tasked with sorting the miscellaneous technologies that was produced in the castle into their designated repositories.
At first glance, the labor appeared mismatched; most beings were merely handling or sorting items rather than forging them, marking them as subservient laborers to the castle's master. The only group that truly demonstrated expertise were those dealing with the exotic plants. Although they were not responsible for planting, they possessed deep knowledge of identifying ripe plants, calculating the precise amount of life energy each could yield, and operating the intricate devices used for extraction. Their work demanded precision, discipline, and mastery, making them officials of their craft rather than mere servants.
Ralph belonged to this group of officials, dedicating himself to extracting life energy and replenishing plants from the first vault. Another striking detail was the sheer abundance of life energy stored here—ranging from small flasks to massive tanks—making the fourth vault a reservoir of unimaginable power, a place where vitality itself was preserved and guarded with utmost care.
***
Frank had no knowledge of what truly lay ahead; he simply stepped toward the passageway leading to the vault. Yet he was not moving carelessly—aware of the traps concealed along the path, he drifted slightly above the ground so his weight would not trigger them. He kept a sharp eye on the hidden cameras that might be recording his movements and avoided lingering in one place too long, wary of sensors that could betray him. His cautious strategy seemed effective, allowing him to advance toward the third floor without hindrance. But just as he neared the location of the third vault, the ground suddenly split open beneath him, and the purple substance he relied on to drift vanished.
Shocked, Frank realized this trap was unlike anything he had imagined. Below him roared a raging inferno, threatening to reduce him to ash if he fell. Stranger still, the trap appeared to be linked to both the purple substance and natural forces themselves, as if designed to sever his lifeline. As the hole widened, Frank desperately tried to summon his drifting skill again, but the purple substance refused to form. His legs slid toward the edge of the expanding chasm, forcing him to leap. By sheer fortune, he landed free and pressed onward. Reaching the third vault door, he reflected grimly on how deadly this trap would have been for soul beings who only knew drifting, and how close he had come to death himself. Grateful for his ability to walk, he struck the vault door repeatedly with his pickaxe until its surface warped and cracked. The door finally shifted ajar, and Frank stepped inside, determined to claim the reward he had risked so much to obtain.
***
While Frank was celebrating his narrow escape from the tongues of fire, another scene unfolded deep within the fourth vault. The trap triggered near the third vault had sounded an alarm, alerting the soul beings stationed on the far side of the fourth vault. Yet when they heard the piercing signal, none appeared disturbed or nervous. Their confidence stemmed from the knowledge that their security system was among the most formidable ever devised.
It could sever the delicate connection a soul being maintained with the natural forces, leaving them unable to move and with only one grim option—to plunge helplessly into the vat of flames waiting below. A few of the soul beings exchanged thoughts, wondering what kind of reckless or gullible intruder would dare attempt theft from any of the vaults. Their suspicions quickly settled on one group: the servants of their master. In their minds, no ordinary soul being would venture so far into the upper vaults, especially when treasures of immense value already lay scattered across the lower, less secure floors. Moreover, they believed no outsider could possibly infiltrate the castle without being tracked by its vigilant cameras and relentless sensors, and such a figure would never be granted clearance to approach the inner rooms ahead. To them, the alarm was not a threat but a confirmation of their system's unshakable strength.
***
Meanwhile, Frank was touring the shelves in the third vault, trying to find the book with the title "Etre". However, finding it was proving difficult; first of all, the book wasn't where he left it the last time he was here in his incorporeal form. Now that he was in his real form, the solid, cold air of the room biting at his skin, he couldn't just put his hand into one of the books on the shelf as he once did.
When trying to find the book, however, after searching a few books that showed the following notifications when he brought them to his face:
[You do not have enough experience to read these.]
He finally came upon a blue book with no name. However, immediately he opened the book to view its contents, the name "Etre" appeared on the cover as if recognizing him and when he laid his eyes on the words of the book, he read:
[And soon, darkness came to taste... like death].
"Taste... like death," Frank repeated the words again, trying to determine the meaning of them to no avail. However, since it had taken him a long time to understand the words on the first death book he read, and sensing the room becoming even colder, he stuffed the book into his bag and proceeded to get out of the castle. However, before he could leave, the section of the shelf the book titled "Etre" was taken from stuffed up and slid upward, revealing a compartment and an absentminded figure coming out of that compartment.