THE FIGURE STROLLED FORWARD, removing a huge black shawl that fell to the floor. Torchlight shimmered over wheat-gold hair and tinted her white gown with an angry light, making her look both celestial and terrifying. Shadows hollowed out her sunken cheeks. She still looked gaunt, but much stronger than I’d remembered from my visit to the ship.

“Marella?” I murmured in amazement.

I glanced at Arcus. He looked shocked, then furious. “I don’t know what you think you’re doing here, but this isn’t a party, for Tempus’s sake. Get out of here before—”

“You always underestimate me,” she broke in, sounding irritated. “You do realize that just because I dress well doesn’t mean I’m a featherbrain?”

“Marella, this is not the time,” I warned. Then, because I couldn’t help myself, I asked, “How did you even get here?”

“Through the tunnels, of course. I had a guide who knew the location of the throne. My own personal shadow.” Though her words made no sense, her tone was relaxed and smooth, as if we all sat at a grand table for a court dinner. “Now, where is the shard? Ah, yes. I sense the tall one has it. Prince… Eiko, is it? If you’d just hand that to me, I’d be much obliged.” She waltzed up to him and held her palm out.

He regarded her in stunned silence.

“I don’t want to hurt you,” Marella explained. “But if you don’t hand over the shard, I’ll have to.”

“Marella,” I said desperately, “what are you doing?”

“I want the shard,” she said slowly, as if talking to a simpleton. She beckoned to Prince Eiko.

“I’m not giving it to you,” he snapped, clearly outraged by this confusing turn of events.

She dropped her hand. “Well, I suppose it’s as good a time as any to test my new abilities.”

She closed her eyes and dark tendrils flowed from her pale hair. A gossamer shadow took form in the air above her. First, its shoulders bristled with protrusions that appeared to be jagged icicles, with similar pointed shapes forming a crown on its head. Then there were hints of a humanlike upper body.

Dread sank talons into my fast-beating heart.

Somehow, the frost Minax was here.

As it hovered in the air, it whispered in a sibilant language I couldn’t decipher, though I could hear the fire Minax answering in the same tongue.

Both of them. Here. No!

Then, to my utter horror, Marella spoke in the same language, as easy and familiar as friends gossiping over tea.

A wash of ice settled at the base of my spine. Arcus was suddenly in front of me.

Terror elongated Prince Eiko’s face, accentuating the bones in his cheeks. “What—”

Marella fluttered a hand at the hovering shadow. “I’m sorry, how rude of me. You don’t understand its language. The Minax said ‘Give us the shard.’” She held her hand out again, palm up. “I hope you’re more willing now.”

We all stared helplessly. The Minax wasn’t something you could fight with frost or fire. It was made of mist and midnight.

“No,” Prince Eiko said shakily.

The shadow creature flowed toward him, its obsidian tendrils disappearing into his hands, which had come up to ward it off. His eyes widened and he jerked a couple of times before reaching, puppetlike, into his pocket and pulling out the shard. He extended his arm and dropped it into Marella’s outstretched palm.

She flashed a smile, as sparkling as a sunlit waterfall and as infectious as typhoid, the one I’d seen charm a roomful of courtiers. “Thank you.”

The shadow creature left Prince Eiko’s body and floated toward me. Arcus sent out a blast of frost that went right through its transparent form.

True vessel, it begged, drawing nearer. I shrank back instinctively.

“Return to me,” Marella commanded, and the frost Minax flowed back into her instantly.

“Marella,” Arcus said, sounding horrified, “how long has that… thing… been part of you?”

“It wasn’t easy,” she said softly. “I had to find it in Tevros. Convince it to choose me as its next host when the previous one—rather conveniently, mind you—died in a brawl over a game of dice. And then there was hiding my… condition… on the ship. Luckily, seasickness is an excellent cover for Minax possession.” Her breathy laugh raised a fresh crop of goose bumps on my arms. “That’s why I had to stay in my poorly lit cabin most of the time. I couldn’t let you see my veins. Also, I truly did feel ill at times, and then I had these strange visions… .I think I saw you, Ruby. In the Fireblood school, and once when you were in a cave or something. There was fire and lava. Did you see me? On the ship?”

“I think so,” I answered, feeling sick. I’d seen someone on a ship. It must have been Marella, or rather the frost Minax that was somehow still connected to me, sending me images she was seeing.

She nodded. “Most people who are possessed don’t survive longer than a week, but I’m stronger than most people.” She glanced at Arcus. “Sometimes at night I sent the Minax into one of your sailors for a few hours to give myself a rest. If you heard someone screaming with nightmares, that would be why.”

A razor-sharp chill skittered over my body, raising every tiny hair on my arms and the back of my neck.

“You’re mad,” Arcus breathed.

“Not mad. Tired. Tired of having to behave like a ninny to fulfill my father’s expectations for what a lady should be. Tired of being underestimated by you and the court. Tired of being passed over. Tired of pretending to be so much less than I am.”

“What are you planning to do?” I asked.

She moved gracefully toward Arcus, whose whole body tensed.

“Arcus, you’re going to step away from Ruby,” she instructed with a small, chilling smile.

“No,” he said firmly.

She moved closer. “You’re going to move away from her now.”

“No!” He lifted a hand to stop her approach.

She stopped inches away. “If you hurt me, if you knock me out, the Minax will merely be free to do as it wishes. You know what follows. Death. Pain. Madness. It will inhabit whomever it chooses and you will have no control over it. I, however, control it perfectly. As you have seen. And by the way, Prince Eiko can stop right now or he will be the first to die!”

She swiveled suddenly, catching Prince Eiko just feet behind her.

“Get back to the wall,” she ordered.

The prince moved to the wall, the rage in his eyes spitting green fire.

“I don’t need you, Arcus, or you, Prince,” she said with a flap of her hand. “You can both leave.”

They didn’t move.

“I can see you’re not taking me seriously.” Her jaw hardened. She pointed at Prince Eiko and the Minax seeped into the air again, then flowed into his body. This time, he gave an earsplitting shriek of agony that echoed off the cavern walls. He dropped to his knees.

I sensed the exultation of the Minax, both of them, as they absorbed the joy of his suffering.

Marella said, “Return to me,” and the shadow arced toward her and disappeared into her veins. “Now that you know what I’m capable of, I suggest you leave. Or should I just kill you?”

Prince Eiko grabbed the wall and hauled himself to his feet, then turned to face Marella again.

“Go, Prince Eiko,” I said pleadingly.

“I brought you here. I won’t leave you.” He brought his hands up, palms tilted at Marella to attack. She watched him, poised. A snake about to strike.

“You can’t fight this with fire, Prince Eiko,” I said. “Please, go now.”

The corner of Marella’s mouth twitched up, as if she enjoyed his indecision.

“Just go,” I repeated. “Please!” Hearing the urgency in my voice, he backed toward the door and, with a reluctant glance, left the cavern.

“Now you, Arcus,” she said calmly, tilting her pert chin toward the entrance.

He shook his head. “Only if Ruby leaves with me.”

Marella closed her eyes, and the Minax came for him, its onyx talons outstretched. He put up his forearm to block. I waited for that sickening moment when the tendrils would penetrate his skin.

Instead, it recoiled visibly, jerking back as if rebounding off an invisible barrier.

Not that one, it whispered, shaken. I felt its revulsion and pain. Shock rippled through me.

Marella’s eyes were narrowed to slits as she examined Arcus, who stood with his arm still raised as he watched the Minax return to her.

She shuddered as it disappeared into her fingers. “I guess I’ll have to let you stay for now. But I think I’ll close that opening, in case anyone else decides to join us.”

Her arm shot forward and frost surged out to strike the ceiling with the force of a battering ram. A deluge of rock shook the floor, clogging the opening. When the ground stopped trembling, she smiled, self-satisfied. “Didn’t think I could do that, did you? The Minax lends me power.”

Arcus and I shared a brief look. She truly was unstable. Weeks of possession by the Minax had tangled the threads of her mind.

“I’ve dreamed of this day for so long.” She smiled benignly. “To reunite them both. I can hardly believe I’ve done it.”

“Why would you want to?” I asked, wondering if her reasons would make any sense to me.

“The frost Minax and fire Minax are like twins. Not only did the frost Minax feel the constriction of its own bonds, it could feel the pain of its twin in the fire throne. The fire Minax was isolated here, kept from its true host, the queen. The best it could achieve was a partial bond, blocked by rock and castle stone. How do you think that felt, Ruby?”

The bond had been strong enough for the queen to execute any Frostbloods who didn’t agree to servitude. I couldn’t imagine what a full bond would look like.

Marella’s eyes were shrouded by shadows, but somehow they managed to glow with a restless fervor—nearly fanaticism—that terrified me almost more than the Minax.

“I could hear it,” she continued. “The Minax speaking to me from the frost throne. My mother’s family worshipped Eurus, the creator of the Minax, though I only found out after her death. My father wouldn’t let me speak to her when she took ill, probably because he knew she’d tell me secrets about the Minax before she died. But I’ll never know for sure, will I? Thanks to his small-minded fear of power.”

“Small-minded fear?” I breathed with disbelief. She spoke as if exposure to the Minax were no great risk.

“Don’t you want the power to control your own life, your own destiny? Having authority over others only makes that easier. I was groomed to marry a king. But when it became clear that would never happen, I was forced to come up with an alternate plan. I will rule. Just not at anyone’s side. I have a much more powerful ally than any king.”

“Who?” I asked.

“It’s time for you to find out. Come here, Ruby.”

“No,” I said. “I know how hard it is to resist the Minax, but don’t let it control you. Don’t let it win!”

“I’m the one who has won.” She opened her hand to show the black shard resting on her milk-white palm. It seemed to absorb the light, making everything around it dim and colorless. “Let me see how well you resist now, Ruby.”

“Give me the shard, Marella,” said Arcus in a low, persuasive voice. “Whatever you think—”

With decisive speed, she dashed the shard against the floor and crushed it under her heel.

The sharp crack was followed by wisps of obsidian mist rising from the shard’s remains. The tendrils coalesced into a roughly humanlike shape. Rising from its brow were several curved points that moved sinuously, like flames. A crown of fire. The fire Minax.

The inky creature gathered itself and twitched toward me.

Arcus moved to block its path. The creature changed direction and slipped around him and behind me, flowing into the nape of my neck like a splash of hot water. I clapped my palm over the vulnerable skin, but the Minax had already seeped in, taking hold, curving into the dark, hidden spaces of my mind and clinging like a bat to a cave’s ceiling.

We are one, the Minax said—or was it I who spoke? It didn’t matter. In seconds, I’d forgotten who I’d been and what I’d wanted. I was whole in a way I’d never been before. I experienced the relief of no longer fighting something inevitable. Fear left my body in an exhalation and loosening of limbs.

I met Marella’s eyes and she smiled. I felt peaceful suddenly. She and I were in tune with each other. Her plans were no longer a mystery to me. If I hadn’t been fighting so hard against my connection with the Minax, I would have known her intentions sooner. Now all that was left was a final joining, to touch my twin for the first time in a thousand years. It could have been a million. Or yesterday. When the separation was over, it would no longer matter.

I moved toward her, arm extended, hand seeking.

The Frost King—Arcus—caught me around the waist and I cried out, hating his very nature, his touch. His essence repelled me, made me writhe and want to leave the safe and perfect shell of the Fireblood girl Ruby—the Daughter of Darkness who had come to free me.

“Ruby!” he said sharply, and I pushed at him, lashed out with hands and feet, drew in breath to wield my fire. His arms tightened like cold steel bands pinning my arms to my sides. I focused on expelling him with a flash of heat over my skin. If I had to burn in order to escape him, I would.

But while he held me, she—Marella, host to my twin—came forward. Her hand sought and found mine. As our flesh touched, cold to warm, my twin and I reached our shadow fingers through our hosts’ skin and touched as well.

A wavelike pulse rippled out into the air, shuddering through the walls, drawing cracks on the stone floor, shearing through sections of the ceiling and pulling down rocks into shivering piles of rubble. The Frostblood was thrown off his feet.

From our linked hands came a bubble of light that swirled and grew larger until a lozenge of blinding white spun between us. All that was left was the recitation of words of power that would complete the ritual. We said them in unison, old words no longer remembered, an ancient tongue only spoken by gods. Saying the words was a joy because it meant we were no longer alone, we had found each other and would soon be reunited with our creator. We would never be alone again.

The Frostblood—Arcus—surged to his feet. A gash on his head leaked blue liquid, the lifeblood of his frail mortal body, and I noted that weakness in case I needed to attack.

“What is that?” he demanded, staring, the white of the portal reflected in his wide-open eyes.

We didn’t respond. We didn’t need to. We didn’t answer to him.

The portal steadied, its borders stabilizing. My twin and I stepped back, our arms falling to our sides.

Moments later, a figure strode through the shining portal, his skin too bright, glowing like moonlight and sunlight and crushed pearls, smelling of spring buds and the wind of eastern storms.

“Who brought me here?” The voice of the east wind was resonant, immense, and implacable.

“We did,” we said.

“And where is my vessel? The mortal body that will host my essence so that I might remain in this world?” he asked.

We lifted our arms to point at the Frostblood man.

“An imperfect vessel,” said our master. “He is bleeding.”

“There is a Fireblood prince in the tunnels,” I offered humbly, hoping that Prince Eiko was still there. I was shivering now in all my human limbs, and in my shadow self as well. To risk his displeasure was to risk great suffering. We had no power over him. We had learned that unmistakably when he put us in the thrones and we’d begged for freedom, for mercy, and found none.

The god of the east wind turned to the tunnels and a bolt of purple light shot from his hands, making us cower and cover our heads with our arms and whine in fear. His light scorched. To let it touch us would be anguish.

The rocks that blocked the tunnel entrance were blown into a cloud of choking dust. When the debris settled, not one, but two figures emerged, their mouths covered by their sleeves.

“Ruby?” one called. Kai. He had hair like a summer sunset. He came closer, waving at the dust that clouded his vision. He froze in shock as he caught sight of Eurus, a being made of glowing light. “What—”

The other figure who followed was tall and dark, his eyes the green of wet leaves. Prince Eiko. He had brought the Fireblood and the Frostblood to destroy my throne.

“There are two of you,” our god Eurus said, his skin too bright to look at. “And I only need one. Who shall be my vessel?”

Neither spoke.

“You, then,” said Eurus, pointing at the bright-haired Fireblood prince—Kai—and I felt a strange bolt of something unpleasant. Some unwelcome human feeling. Fear for another’s safety. It was my host who made us feel this unpleasant thing. We didn’t want him to hurt Prince Kai with the hair of glowing coals and the eyes of golden brown.

Eurus moved toward the mortal.

“Wait!” The sound had come from my own mortal throat. The part of me that was still Ruby had surprised me, taking control. “Take the other one.” I spoke without wanting to, without thinking, and then trembled in fear of the god’s wrath.

But Eurus was merciful for once in an age, and he changed direction and slid into the other body, the tall man. Prince Eiko’s green eyes turned white for a moment as the light entered his thin body, then returned to normal.

Eurus-Eiko turned to the sunset-haired man. His expression spoke his intentions clearly. Our god had no use for Kai and so he would get rid of him.

We struggled with ourselves, the Daughter of Darkness trying to assert her consciousness.

“Kai!” Ruby’s will once again took control of our voice. “Go! Run!”

Kai shook his head, his gaze flinty as it latched on to Prince Eiko—Eurus. “You are no longer Prince Eiko. Are you?”

“Eiko is gone,” said Eurus.

“Then I don’t have to worry about hurting him,” said Kai. The bend of his knees, his wide-legged stance and posture all screamed his intention to fight.

“Kai, no!” I called out.

Fear had brought me partially back to myself, but the Minax struggled for dominance, bathing my mind in a cocktail of sweet numbness and a sense of futility. What does any of it matter? the thoughts said. Everything is fine.

I forced myself to focus on Kai and Arcus, on memories of my mother and grandmother, finding the parts of myself that feared and cared and hurt. I rejected the floating joy the Minax offered and grabbed at thoughts of affection, empathy—even grief. Every second was a power struggle between myself and the Minax. I phased in and out of awareness as a separate entity.

I was pulled from my self-absorption as fire flew from Eurus’s fists, or rather it was Prince Eiko’s fire coming from fists he no longer controlled. The attack caught Kai off guard, throwing him backward. He slid across the floor for several feet before coming to a stop. I took a step toward him, relieved when I saw his chest rise and fall.

“Leave him,” said Eurus. “He is of no consequence.”

I jerked to a halt. Arcus had moved beside me. Eurus’s gaze sharpened on him. If he meant to do to him what he’d done to Kai…

Fear broke through the remaining mist in my mind.

I’m Ruby, I thought, beating away the velvety layers of numbness wrapped around me, wresting my identity from the mind of the Minax. I’m in control.

I must have spoken aloud, because Eiko—Eurus—smiled condescendingly. “You are no longer merely a simple Fireblood girl. You are something more now. And though you will not live long enough to see the final triumph that comes from your sacrifice, your life will be given for a greater purpose. You will serve as host for the Minax as we travel to the Gate of Light. And when my Minax destroy the sentinels, I will break the bars that keep the Gate closed, so the rest of my living shadows will pour from where Cirrus trapped them in the Obscurum. So, you see? You’re not dying in vain. You’ll be remembered by the gods.”

“As the one who helped you unleash the Minax on the world?” I asked, more fully myself for the moment. “That’s not how I want to be remembered.”

His green eyes narrowed, but his smile widened. “Somehow you’ve retained more than a little of yourself, haven’t you? Remarkable. The Minax chose a strong host.”

The Minax inside me grew excited, murmuring something about a true vessel and Daughter of Darkness, and though I was careful not to form the words with my lips, I sensed that Eurus could hear its voice anyway.

He lifted a brow. “Are you certain, pet?”

The Minax eagerly answered yes, and then the heart-shaped scar near my left ear burned. I clapped my fingers over it, but Eurus stepped closer, grasped my wrist, and drew my hand firmly away. His eyes met mine, and even in the dim light, they looked brighter green than ever. “There is only one person on this earth my Minax would mark this way.” His eyes seemed to glow.

“You are my daughter.”