We descend from the surface of Mount Etna, following a narrow path that spirals downward into the crater. Each step takes us deeper into a world that feels increasingly alien—a realm where the normal rules of nature bend and blur beneath the volcano’s ancient power.

“Stay close,” Riven says to me, one hand on the hilt of his sword and the other reaching for mine, as if he’s afraid he might lose me if I move too far away from him.

Thalia leads the way, her grief giving her reckless courage as she descends into the inferno. Water swirls protectively around her, but even that isn’t enough to shield her from the blistering heat.

The further we descend, the more bizarre our surroundings become. Vents in the volcanic rock release plumes of steam that glow with eerie red light. The air becomes thick, my clothes sticking to my skin, each breath a conscious effort.

“By the gods,” Thalia gasps as we round the final bend.

Riven and I come to a sudden stop behind her. Because before us stretches a vast chamber—the heart of the volcano.

It’s breathtaking. Magma flows in glowing rivers across the floor. The ceiling arches impossibly high above, and the walls are solid obsidian, polished to a mirror shine, reflecting our images back at us in twisted, dancing patterns.

I’m barely orienting myself when the ground rumbles and the floor cracks, lines of magma seeping through like veins of molten gold.

In an instant, the Star Disc is in my hand, its energy pulsing in rhythm with the tremors beneath our feet.

Riven steps closer to me as three distinct mounds emerge from the magma pool.

They glow red-hot, cooling as they take form, as if sculpted by invisible hands into… ourselves.

But they’re not us. Not really. Because the me I’m looking at is one I’d recognize anywhere. She’s the twisted version of myself from my nightmares. As always, her eyes are empty, devoid of conscience or remorse, and her hands and arms are coated with dried blood .

Next to her stands a corrupted version of Riven. The Lonely King, but twisted into something fiery and cruel. His eyes burn with malice, and his crown is hot magma instead of ice, veins of red spreading under his feet in jagged, threatening patterns.

A pained whimper sounds from Thalia’s throat, and I follow her gaze to see Maeris directly ahead of her. But like the versions of me and Riven, Maeris is wrong. His features are twisted into a mask of hatred, his stance aggressive where it had once been loyal and protective.

“This can’t be real,” Thalia says, water surging around her in chaotic waves.

“It’s not,” Riven says, but his voice lacks conviction, his gaze locked on his dark counterpart.

Suddenly, the floor between us splits, and I stumble backward as the ground beneath me rises, separating from the main floor to form a floating obsidian platform. Across the chamber, Riven and Thalia experience the same, each of us now isolated on our own dark island in a sea of molten rock.

“Riven!” I call out, but my voice is swallowed by the rumble of shifting stone and hissing magma.

Movement nearby snaps my attention back to my immediate surroundings.

The shadow version of me is on the opposite edge of my platform, perfectly still, watching me with those dead eyes. Blood drips from her fingers, sizzling when it hits the stone.

My Star Disc pulses in my hand. Not in warning, but in recognition. As if my weapon knows this twisted version of myself as well as it knows itself.

The other me doesn’t attack.

“What do you want?” I ask, staying grounded, ready to throw the Star Disc in a perfect arc to slice her throat if she does so much as raise a finger against me.

She lifts her hand, and a shadow version of my Star Disc materializes in her palm, sparks of fire trailing from its edges. Just as sharp. Just as deadly.

“Fine,” I mutter, channeling my magic into my Star Disc— Glimmercut, I affectionately remember Riven and I naming it together. “Let’s see what you can do.”

I throw the Disc with all my strength, sending it spinning toward her chest, ready to end this.

She doesn’t dodge. Instead, her hand snaps up, catching Glimmercut mid-flight, her bloodied fingers closing around the edge without cutting her flesh.

Her empty eyes meet mine, and then she’s sending it hurtling back toward me with equal force.

Just like she did, I catch it. And before she can attack again, I dig inside myself, reaching for my water magic, sending a pressurized blast surging at my shadow self’s chest .

She instantly—not with water, but with fire—meets my magic in the middle.

The collision creates a spray of scalding droplets that rain down between us, hissing where they hit the stone.

I switch to ice next, coating Glimmercut’s edge with frost so cold it steams in the volcanic heat before I charge forward, slashing at the twisted version of myself with calculated precision. But once again, she matches me perfectly, her own weapon gleaming with heat that melts my ice.

Through the steam of our clashing powers, I glimpse Riven across the chamber, locked in combat with his dark reflection. Ice and water magic collide in spectacular bursts as he fights with all the skill and power of the Winter Prince.

He’ll be okay. I saw the sheer force of him while we fought the fire monster together, when he was driven to kill and destroy for his love for me.

Assuming his shadow self doesn’t share that love—which is slightly disturbing to think about—I have full faith in him that he’ll come out of this victorious.

Beyond him, Thalia faces her corrupted Maeris, her attacks desperate and wild, driven by grief rather than strategy.

My attention snaps back to my own battle as my shadow catches my wrist, stopping my attack mid-swing. Her grip is like iron, cold despite the infernal heat surrounding us. Up close, her eyes are worse—like looking into empty wells where something vital should be.

I break free with a surge of air magic, pushing her back several steps. But she doesn’t stumble. She doesn’t blink. She just smiles. That same empty, blood-slicked smile from my nightmares.

“Why won’t you speak?” I demand, circling her once more. “What are you trying to tell me?”

She resumes mirroring my movements, silent, waiting for my next attack.

After several more exchanges—each as futile as the last—I stand panting, blood covering my skin from dozens of small wounds that heal almost as quickly as they form.

My shadow remains pristine. Untouched. Untired. Apart from the blood that coated her from the beginning, she’s perfect. Inhuman.

She’s everything I fear I could become.

The metallic scent of blood fills my nostrils, bringing with it memories of the dark angel, of all the animals I’ve killed since my vampire side awakened, and of Riven’s life force flowing into me as I fought to save him in the Cosmic Tides.

Panic rises in my throat as I stumble back, barely avoiding another slice of my shadow self’s Star Disc.

“You’re not real,” I say again, louder this time, my voice echoing across the chamber. “You’re what I fear becoming, but I’m not you. I’ll never be you.”

The shadow pauses, her head tilting slightly, as if considering my words.

Then, she raises her fiery version of Glimmercut and throws it, the weapon spinning toward me with deadly precision.

Instead of dodging or trying to deflect it, I lower my arms and stand tall.

“I choose my fate,” I say, staring straight into those empty eyes. “Not you.”

The Disc strikes me, cutting deep across my chest.

Pain explodes through me, fiery agony, cutting deep into my soul.

I’m only halfway aware of my scream echoing through the chamber, unsure if I’m truly capable of making a sound as raw and primal as the one I hear.

But through it all, I remain standing, blood soaking the front of my clothing.

And as the wound begins to heal, Glimmercut—both hers and mine—vibrates.

Gripping my Star Disc tighter, I channel all my elements at once, the power rushing through me so strongly that I can barely see straight.

My air magic lifts me slightly off the platform. Water coats Glimmercut in a shimmering layer, ice sharpens its edges, and finally, I add my star-touched will—the cosmic energy Celeste bestowed upon me .

“You don’t control me,” I say to my shadow self, throwing my star forged weapon one final time.

The Disc cuts through the air with blinding speed, trailing not just stardust, but a combination of blue and yellow magic—ice, water, and air.

It strikes her in the heart, and her normally empty eyes widen as cracks spread across her form, light spilling from within. She staggers, reaching toward me with one hand, and then she shatters into obsidian dust that scatters across the platform, flecks of it blowing into the magma below.

My platform stabilizes, the edges solidifying as the magma recedes.

Glimmercut returns to my hand, humming with satisfied energy.

“I know who I am,” I whisper to my deadly, gleaming weapon. “I’m Princess Sapphire Hayes Fairmont Solandriel Draevor of the Summer and Winter Courts, the New York Vampire Clan, and the chosen Star Touched warrior of Celeste—and I choose my own destiny.”