Clouds roll over Felwinter Peak. Wind scours the cliffs, sending snow hissing across the stones and ripping at Osiris’s robes. The thin air tastes of ice and lightning.

When the wind picks up, Osiris shelters in the lea of a weathered stone. He tucks his knees up to his chest and takes an inventory of his body—the frostbitten numbness in his toes and fingers, the ice gathering on his brows and lashes. His core temperature is well below normal, and has been for some time. Hard to tell what’s pushed him this far: stubbornness, or that paradoxical feeling of warmth that signals hypothermia.

His body is dying. “Sagira,” he says. “Stand by to resurrect me.”

“Not again,” she groans, but still she lends him the Light to forge a sword of sunlight.

The heat of it strikes his numb body like a thousand blunt blades. He gasps as dying nerves awaken and kindle into pain; his stiff hand can barely curl around the hilt, but still he bends to that radiant flame as though he is a flower seeking the sun. The warmth on his face makes grateful tears spring to his eyes, and for one glorious moment, they do not freeze immediately in his lashes.

Then he braces his hands and drives that blade through his chest.

When he rises again, the cold burns at his fingertips, even through his gloves. He pulses solar heat through them, and Light wells up in his cupped palms until he overflows with it. While the wind claws at the cliff face just beyond his shelter, he sits in meditation, pressing the heels of his hands to his cheeks, his chest, his boot-clad ankles. No matter how much Light he gathers to himself, though, the warmth always bleeds away.

Overhead, the promised storm breaks at last. Snow blows down in sheets of swirling white; distantly, Osiris sees lightning break the dark blue-violet clouds, and he hears the roll of thunder.

He sinks deeper into the crevice in the rock, deeper into himself. He lets the darkness behind his eyes fade into a deeper blackness, and sets himself adrift in the void between the stars.

Infinite wheeling galaxies pass him by, melting like snow and leaving only shadows behind. The cold emptiness carves him down to almost nothing—stripping away body and sense and history, and leaving only a single, focused point of intention like a candle flame.

He feels himself flickering in the face of that vast nothingness. It flows past him and through him, a lightless, bitter torrent without source or ending; it could snuff him entirely and never notice his absence.

And yet in that boundless darkness, there is a distant light. It beckons him in, a lighthouse amid fathomless seas, and he lets himself be borne toward its glow. He fixes himself on it as though it is a mirror, magnifying and strengthening his own light.

“Osiris,” Sagira says, against his ear and trillions of miles away. “Osiris, your vitals are getting kind of low. Maybe a little heat? Osiris?”

He ignores her. Time and space bend toward that point of light, the locus of his universe. He drifts toward it on solar winds, riding the ejecta of stars, skimming across the interstellar medium like a stone skipped across a still pond.

He is nothing but light and longing, caught in the orbit of something beyond understanding, and he craves the moment of collision more than he dreads it.

* * *

When Osiris wakes at his next resurrection, he has to brush away a thick blanket of snow. The air is still; the clouds above have faded to a high, fine grey.

Sagira nudges against his hand. “You should’ve sent one of your reflections,” she says. “The cold doesn’t bother them.”

“Lord Felwinter would not come down from his mountain for the sake of my reflections,” Osiris answers. “He respects strength.”

“And stubbornness?”

“And stubbornness,” says Osiris. He gathers himself up and opens a rift at his feet, letting it warm him and invigorate his aching bones. One would think that dying would prevent the aches of an uncomfortable night’s sleep, but one would be wrong in that respect.

Hunger gnaws at his empty belly, licking the undersides of his ribs. He ignores it.

Slowly, he begins to climb the mountainside again. In some places, the path is broken, and he clings with fingertips and toes to keep his footing on the treacherous rock. In other places, he can only leap from ledge to ledge and trust his Light to keep pushing him upward.

Through the blowing snow, he glimpses delicate towers, bridges and buttresses. A radio tower with snow piled high in the dish. Someone standing on a parapet, watching him climb in silence—but when he looks again, he sees only snow sweeping the battlements.

He heaves himself onto a ledge barely thicker than two fingers, and there, he contemplates the sheer cliff face above and to every side.

There is no way up from here. He will have to go back and find another way.

Something keener than rage wells up in him. A mountain will not best him. Lord Felwinter will not best him. Not after he has come so far. He gathers all of the Light in him and leaps—then at the height of his arc, he unsheathes a blade of sunlight and jams it into the mountainside. A radiant sphere of Light bursts around him; rock melts and pours down the cliffside in white-hot rivulets.

Osiris pulls himself up onto the sword and leaps once more, and this time, he touches down on a smooth plain of snow. His booted feet melt through to the flagstones below.

Before him stands a slender Warlock, arms folded, dressed in a tattered dark coat and a horned helm. He is smaller than Osiris expected—compact, like a clenched fist. He tips up his chin in acknowledgment as Osiris lets the Light fade from his hands.

Osiris pulls down his mask and gathers his feathered cloak around himself. “My name is Osiris,” he says. “I’ve come to request to train under Lord Felwinter.”

“You have my attention, Osiris,” says Felwinter. His voice is mild, inflectionless; somehow, it cuts deeper than the wind. “I’m not sure you realize how dangerous it is to have my attention.”

* * *

The fortress on Felwinter Peak sprawls across the mountaintops, its slim towers joined by vaulting bridges and buttresses—some hewn of stone, some forged of steel, all of them sharp and delicate as blades. Osiris can’t help feeling as though he is surrounded by a host of silent sentinels, looming out of the gloom and the snow.

Felwinter flings open the double doors of his entrance hall, and warmth spills over the threshold in waves. Hearty fires blaze in the braziers lining the hallway, their warm light limning Felwinter’s helm and shoulders in gold. Tapestries shift in the breeze, and the light catches on the metallic thread worked through them in rhomboids and angles. Beautiful, yes, but not only beautiful; Osiris recognizes circuitry woven through each panel of fabric, lending processing power to some larger computational engine that he cannot begin to conceive.

“You built all of this,” says Osiris, looking up to the high arched ceiling.

“You don’t sound impressed.”

Osiris dips his head. Indeed, the fortress does not impress him. Many warlords have built grand monuments to their own pride and folly, usually with the labor of those weaker than themselves. He has seen their palaces, their palisades, the heads mounted on pikes at their walls. The scorched shells of Ghosts inlaid into mosaics, along with teeth and earrings and shards of Exo plating—monuments to their glory built from their fallen foes.

At last, Osiris says only, “I was curious as to its purpose.”

Felwinter makes a faint, rough sound that Osiris barely recognizes as a laugh. “My enemies are also curious. Keep wondering.”

Far, far below, the bells of the Iron Temple toll the hour. A wolf gives an abortive howl, more than half a yawn, but the pack soon takes up the call. Soon closer voices rise in echo, until even the high peaks ring with their music.

Perhaps the howls of wolves should make Osiris shiver, but instead they hearten him. They remind him that even in this grim fiefdom of ice and wire, something yet lives.

Felwinter gestures Osiris into a meditation chamber, where patterns of dots flicker across the walls in a rhythm more like language than music. Code, Osiris thinks; given time enough, he could interpret it. He seats himself at the oak table, allowing Felwinter to sit at its head. Above Felwinter’s shoulders, signals coalesce and melt into incoherency: peripheral, agnostic, pharyngeal, chasmic. Modifiers without a referent.

“You came to study under me,” says Felwinter. He presses his fingertips together and regards Osiris over them. His eyeless helm gives nothing away. “What made you think that was a good idea?”

“Nirwen recommended you to me,” Osiris answers. “I studied with them for several weeks at the Iron Temple, but they could not provide the answers I seek. They thought your guidance might prove … clarifying.”

“They grew tired of you.” For the first time, amusement creeps into Felwinter’s voice. “So they pawned you off on me.”

“We had a different fundamental understanding of the Light.”

“They found you insufferable and inflexible. Unwilling to be taught.”

“I am willing to be taught.”

Felwinter leans forward; elution darts between streams of code like a fish between reeds. Osiris cannot help feeling as though he is being sifted to see what he is made of. “A challenge will not bait me, Osiris,” he says, the name an intimate hiss. “Why should I take you on, if Nirwen could make nothing of you?”

Osiris does not drop his gaze. He has wondered the same thing, in the long journey to the top of the peak—whether there is anything that Felwinter can teach him. Whether the knowledge that he craves, or the method for attaining it, is something that can be taught. “I’m adept at solving problems,” he begins.

“So I saw,” says Felwinter drily. “A sword for every problem.”

“If you don’t want to teach me, then say it!” Osiris snaps.

For a moment, the room is silent. Osiris’s voice rings from the walls, louder than he had imagined; his pulse pounds in his ears like a constant roll of thunder.

Felwinter sits back, chin raised, knees splayed. He lays his hands flat on the table. “You think I’m searching for how I might use you,” he says. His voice is cool and blade-sharp. “Don’t presume to know my needs. I see your curiosity. I see your intelligence. You came here seeking an answer that you could find nowhere else—at least have the nerve to ask the question.”

Ire still burns in Osiris, so hot that his chest roils and his skin feels tight. He breathes in through his nose. Deep, steadying breaths; he can almost hear Nirwen counting down from seven at the top of each inhalation. Slowly, the simmering anger and frustration melt away, leaving a core of dull, aching pain that will not fade no matter how long he sits in meditation. “When I reach out into the darkness,” he says softly, “I feel the Light of the Traveler like a distant spark. And it sustains me, but it grows no closer. The more I look to it, the less I see of it. The more aware I am of the void all around me, hungering.”

Felwinter is still, in the way that only an Exo can be still; only the faint hum of his internal machinery gives away that he is alive at all. “You aren’t interested in a philosophical answer.”

“No. It does not suffice to hear platitudes of false equivalence between the distant Light and encroaching Darkness. I am not seeking mere faith wrapped in metaphors. This is not a metaphor or a parable—it is an observation. It must be interrogated as such.”

The meditation room’s lights shift, white to a soft red-golden. Osseous, the patterns whisper; aphotic. Aureate. Osiris wishes he could halt the stream of signals for long enough to ravel back through their syntax, to unweave the nested subclauses until he reaches a core of subject and object and verb.

At length, Felwinter rises. “I see why Lord-and-Lady Nirwen sent you to me,” he says. “If you plan to study under me, you should expect no answers.”

Osiris nods. In the sleeve of his robe, he feels Sagira nudge against his palm, warmly pressing the corners of her shell into his hand. “What should I expect?”

“Questions,” says Felwinter. “Observations. And choices as to what they mean.”

It isn’t the answer that Osiris wants. More than anything, he wants someone to say, There is an ineluctable truth, and it does not change whether or not it is observed. There is a fixed point around which everything turns, and it is not an object of faith but of fact.

He closes his hand on Sagira until his bones ache along her edges, and he says, “When do we start?”