The leviathans swam west through waters still warm from the nuclear detonations, their massive bodies displacing currents that pushed against the poisoned surface.
Nulls crouched inside the serpent's mouth, his body pressed against the creature's hot tongue, watching the grey sky through the gaps in its teeth. Snow continued to fall, each flake a small white flower of radiation that melted against the serpent's scales before it could reach him.
He had no way to measure how long this journey would take. The ocean stretched endlessly in every direction, its surface churned by storms that had no beginning or end.
The mountain pulsed with dim light behind them, its beams cutting through the waves like searchlights searching for threats that had already fled.
The tower flowed alongside the serpent, its thousand mouths opening and closing in patterns that might have been counting the seconds, the minutes, the hours.
Waiting accomplished nothing. His Nexus reserves sat near empty, the last traces of power clinging to his cells like water to dry stone. The sigils on his body had dimmed to faint outlines, their colors faded, their purpose suspended until he could feed them again.
He closed his eyes and reached for the connection that bound him to Yog.
Black fire swallowed the grey sky and the churning sea, replacing them with shelves that stretched into infinite darkness.
Nulls stood on stone that felt warm despite the cold of the transition, his body whole again free of the burns and the exhaustion and the slow drain of his failing reserves. A fireplace crackled somewhere ahead, its light the only illumination in the vast library.
Thousands of books lined the shelves, their spines unreadable in the dancing shadows. Some were thick enough to crush a man, others thin as a child's finger, all of them filled with knowledge that no human mind could comprehend.
The air smelled of old paper and ancient dust, of something burning and something cooling, of the space between stories where truths hid in the gaps.
Yog sat in a chair beside the fireplace, its form still composed of black fire that consumed nothing and produced no heat.
The Codex held a book open in its lap, the pages turning without being touched, the text shifting as it read. The being did not look up at Nulls's approach, its attention fixed on words that glowed with their own internal light.
Nulls stopped a few feet from the edge of the fire's glow, watching the pages turn.
Yog's head tilted slightly, and the book closed. "You came to me of your own will. That has happened only once, when you needed help when they held you captive. What brings you now?"
A chair materialized beside Yog's, identical in shape and size, its cushions the color of dried blood. Nulls walked to a nearby shelf and pulled a book at random, the volume heavy in his hands, its cover rough with age. 'Ladder of Physicalism and the Vermins That Climbed Them', the title read in letters that seemed to move when he focused on them.
He sat in the conjured chair and opened the book to a random page, the text blurring into nonsense as he scanned it. "I need to know how to refill my Nexus reserves. The battle below the city drained me completely, and the radiation on the surface prevents me from hunting for food or rest."
Yog leaned back in its chair, the black fire of its form crackling softly. "There are two methods available to you now. Neither is pleasant. The first requires you to consume living flesh. Every creature that draws breath carries Aetherion in its cells, and I have altered your digestive system to convert that Aetherion into Nexus. The energy must enter your body as solid matter, so drinking blood or swallowing raw meat alone will not suffice. You must eat the flesh of your enemies, chew it, swallow it, let your stomach break it down into the components that fuel your power."
Nulls turned a page, the text still refusing to resolve into meaning. "And the second method?"
Yog's form flickered, the black flame dimming for a moment before flaring back to its full height. "The Rite of Reclamation. It is a ritual that requires precision, fresh blood, and the bodies of the recently slain. You draw a pentagram using blood from a living source. The younger the source, the more potent the channel. The shape must approach a perfect circle, for deviations weaken the binding. You use your claws to inscribe the lines, each stroke deliberate, allowing the crimson fluid to pool in the grooves of stone or earth. The pentagram becomes a conduit that aligns with the underlying structure of Nexus absorption."
Nulls closed the book and set it on his lap. "What else?"
"Around the pentagram, you arrange the corpses in a circular pattern. They must be placed equidistantly, each one a node in the circuit. The bodies can be human or Morbus or any creature with sufficient life force. Those with higher Aetherion yield more Nexus, and arcanists make the best offerings because their bodies have been saturated with power over years of practice. You stand in the exact center of the pentagram with the Codex resting on the ground before you, its cover facing upward, the ancient sigils on its surface pulsing faintly."
Nulls glanced at the Codex, which had materialized on the floor between the two chairs. Its cover gleamed in the firelight, the symbols etched into its surface writhing slowly.
"Then you take a living organism in your hand, something that still breathes and feels. A creature that has not yet died, that still has the spark of life in its veins. You expose its throat and cut through the windpipe and the vessels beneath with a single stroke of your claw. The blood spurts onto the Codex and into the pentagram's grooves, mingling with the blood already there. You chant four lines as the life drains from your offering."
Yog's voice dropped lower, and the black fire of its form pulsed in rhythm with the words.
"The Lurker beyond the Threshold. The Tome and the Knowledge of the gate. The All-in-One. The One-in-All. Each phrase is a key turning in a lock, first invoking the principle that separates this reality from the void where Nexus pools, then calling upon the Codex's own nature as a gateway, then aligning the sacrifice with the unified source, and finally sealing the circuit to draw the released energy inward."
Nulls traced the cover of the closed book with his finger. "What happens after the chant ends?"
"The blood on the pentagram begins to glow with deep violet light that spreads across the lines and into the corpses. The bodies shudder as their remaining life force and any stored Aetherion are drawn out as threads of light that converge on you. The Nexus flows into your body through the Codex, filling the vessel that carries your consciousness. The process burns, a cold fire that sears your nerves and leaves you gasping, but the reward arrives immediately. Your reserves swell, replenished by the quality and quantity of your offerings."
Yog leaned forward, the black fire of its face casting strange shadows across the library floor. "When the ritual completes, the corpses collapse into grey ash. The pentagram's glow fades, leaving only the scent of ozone and burnt copper. You stand in the center with your breathing ragged and your Nexus restored. The Codex grows warm against your chest, its hunger momentarily sated."
Nulls nodded slowly. "What are the limitations?"
"You cannot perform the ritual arbitrarily. The blood and corpses must be fresh, and the location must be suitable for the geometry of the binding. Sacrifices with high Aetherion yield vastly more Nexus, but any living thing will serve in a crisis. The Codex may reject offerings tainted by incompatible energies, though I cannot predict what those energies might be until you attempt the offering. The process leaves you vulnerable, as the drain on your body during the transfer is immense, and you will need time to recover before you can move or fight."
Nulls stood and placed the book back on the shelf, its spine disappearing into the darkness between two thicker volumes. "Then I need to find fresh corpses. Beings that have died recently but still hold enough residual Aetherion to fuel the ritual. And I need to do it before my reserves drop so low that I cannot maintain my body."
Yog returned to its reading, the pages of its book turning without touch. "That is your task, not mine. I have given you the information you requested. The rest is execution."
The fire crackled in the hearth, sending shadows dancing across the endless shelves of books. Nulls sat in the conjured chair, the leather warm beneath his claws, the weight of the closed book still heavy in his lap. Yog had returned to its reading, the pages of its volume turning without sound, the black fire of its form flickering in the rhythm of the flames.
"I have another question," Nulls said.
Yog's head tilted slightly, the motion almost imperceptible. "You came here with one question. You received your answer. Now you ask another. This is unlike you."
Nulls set the book on the arm of the chair and leaned forward, his elbows on his knees, his hands clasped together. "The echelons. How do I advance through them? I am at the second echelon now, but there are nine more above me. The humans at the first echelon, the ones below me, they are weaker than I am. But the ones above me, the ones I have not yet reached, they are stronger. I need to know what stands between me and that strength."
Yog closed its book, the cover snapping shut with a sound like a distant thunderclap. The black fire of its form pulsed once, twice, three times, and the Fireplace flames dimmed in response. "The echelons are not earned through training or study or the accumulation of power. They are granted, one at a time, in exchange for tribute."
Nulls's claws tightened against his palms. "What kind of tribute?"
"One billion souls," Yog said, its voice flat and absolute. "Killed with malice. Their deaths must be horrifying. Not quick nor clean nor merciful. They must feel the end approaching and taste their own fear, You must make them understand that something has chosen them and that nothing will save them. All of the suffering must be real, and you must be the source of it."
A billion souls. The number sat in Nulls's mind like a stone dropped into still water, the ripples spreading outward in concentric circles of calculation. The humans of this world did not number that high in a single city or a single region or even a single continent. He would need to travel far and kill often, and every death would need to be a performance of terror rather than an act of efficiency.
"Once you have gathered all of it," Yog continued, "only then will you become fully Echelon Ten. Not before. Not faster. There are no shortcuts, no exceptions, no substitutions. One billion souls, each one taken in horror, and then the next echelon opens to you."
Nulls opened his mouth to speak, but Yog raised one hand made of black fire, the fingers spreading in a gesture that silenced him before he could form the first word.
"I have questions of my own," the Codex said. "About your beasts. The ones you summoned in the void, the ones you reshaped into forms that should be impossible."
Nulls closed his mouth and waited.
"One of the abilities I bestowed upon you was the power to summon shoggoths, creatures that you could reshape as you see fit. I have watched wielders come and go for longer than this universe has existed. I have seen them use shoggoths as laborers, as soldiers, as shields, as weapons. I have never, in all that time, seen any of them reshape shoggoths into the abominations you have created."
The black fire of Yog's form dimmed, and the library grew colder. "The creatures you summoned are not simply reshaped. They are reinvented. Their forms, their functions, their very existence in this reality comes from a place I do not recognize. They are influenced by something inside you, something innate, something that predates our contract."
Nulls kept his face still, his expression blank, his body relaxed. "Pardon?"
Yog rose from its chair, the black fire of its form flowing upward like smoke caught in a reverse gravity. The Codex walked around the hearth, its footsteps silent on the stone floor, and approached Nulls's chair. Nulls remained seated, his hands still clasped, his breathing steady.
The black fire figure stopped directly in front of him, blocking the light from the Fireplace, casting Nulls into shadow. Then it leaned down, its featureless face inches from his own, and Nulls could smell something burning, something ancient, something that had been waiting in the darkness between stars before the first star ignited.
"I need to know what your innate knowledge contains," Yog said, its voice soft now, almost gentle. "I need to go deeper than your conscious mind, deeper than your unconscious mind, down into the very core of your soul. I need to see what you are hiding, whether you know you are hiding it or not. But I cannot do this without your consent. Invading your core without permission would destroy our contract and leave us both damaged beyond repair."
Nulls leaned backward in his chair, away from the heatless flames, away from the presence that pressed against his skin like a physical weight. Yog followed him, maintaining the distance between them, closing the gap with each inch he retreated. The chair creaked under the strain of his posture.
"All I need," Yog said, "is your word. Say yes, and I will enter you. Say no, and I will return to my chair and never speak of this again."
Nulls forced his body to relax, forced his spine to straighten, forced himself to meet the featureless face of the Codex without flinching. "What would you see? What would you find, once you are that deep?"
Yog straightened its posture, standing to its full height, and the black fire of its form rose with it. "I would see everything you have ever done in this physical body. Every secret you have kept, every thought you have conjured with this brain, every sin you have committed since the momment you left your mother's womb. I would see you, truly see you, with no mask and no facade and no protection. And you would relive those moments, forced to experience them again as I witness them."
A bead of sweat rolled down Nulls's temple, catching the light of the Fireplace's flames before dripping onto his shoulder.
Yog raised one hand and touched its own chest, where a heart would beat if it had a heart. "I have seen unspeakable things from my previous wielders. I have watched atrocities that would break your mind to witness, not because they are great in scale but because they are human in their cruelty. I have never judged any of them. I have never spoken of what I saw to anyone, not even to the wielders themselves. What you have done, what you have thought, how you have sinned. None of it, I guarantee you, would budge me."
Nulls wiped the sweat from his temple with the back of his hand, the motion slow and deliberate. He had done so little in this body. He had killed, yes, and he had bargained, and he had made deals that would cost millions their lives. But he had not done enough, thought enough, sinned enough for Yog to find what it was looking for. The things that mattered, the things that defined him, were not stored in this brain or this body or this lifetime. They were somewhere else, somewhere deeper, somewhere that even Yog could not reach without breaking its own rules.
He nodded, the motion hesitant at first, then firmer. "Yes. Do it."
Yog raised its arms, and from its back, four needle-like appendages unfolded.
They were thin and long, each one ending in a point sharper than any human weapon, and they moved with a liquid grace that made Nulls's skin crawl. The needles spread outward like the legs of a spider, reaching around his chair, positioning themselves at four points around his skull.
"The experience will be strange," Yog said, its voice coming from everywhere now, from the needles, from the Fireplace, from the walls of the library itself. "I need you restrained so that you do not harm yourself. The body sometimes reacts 'uniquely.' to the intrusion."
The needles touched his forehead, his temples, the base of his skull, and Nulls felt cold where they pressed against his skin. The cold spread inward, sinking through flesh, through bone, through the layers of consciousness that separated his waking mind from the core of his being.
Yog leaned closer, and the black fire of its form filled his vision completely.
"I will see you now," the Codex said. "I will see all of you."