The Citadel of the Cŵn Annwn wasn't a castle perched on a hill. It was the hill. The Black Mountain, Y Mynydd Du, had been hollowed and re-forged over millennia into a fortress that pulsed with old, cold magic. Their car passed through a waterfall that fell upwards, through a veil of illusion, and into a cavernous garage lit by glowing, moss-covered sconces. From there, a silent lift of polished basalt took them deep into the heart of the living rock.
Their "quarters" were not rooms; they were a suite of caverns artfully sculpted to mimic luxury. A flowing stream provided water. Glowing crystals, cultivated like crops in wall niches, provided a constant, shadowless light. The furniture was modern, minimalist, and obscenely expensive, rooted into the stone floor. It felt less like a home and more like a very high-end prison exhibit.
"The king welcomes you to your ancestral heritage," Rhys said, his voice echoing in the vast space. "You will find everything you require. Your training begins tomorrow at dawn. The young Dyad will report to the Crucible. You," he glanced at Jonas and Maria, "will be given a tour of the citadel's amenities. Your… input… on the Dyad's progression will be welcomed in weekly consultations."
The dismissal was clear. The twins were assets to be processed. The parents were guests to be managed.
That first night, huddled on a ridiculously comfortable sofa that felt alien, they made a pact in whispers.
"Whatever they teach us,we learn it twice," Erik murmured, his eyes scanning for unseen listeners. "Once the way they show us. Once the way we can use it against them."
"Take everything,"Kaitlyn agreed, her jaw set. "And give them nothing real."
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Dawn in the mountain was a theoretical concept. A chime sounded through the suite. The Crucible was a vast, cylindrical arena deep in the mountain's bowels, its walls lined with tiered stone benches that were always empty. The air smelled of ozone, blood, and dried herbs.
Their trainer was a man called Gareth, built like a cliff and with a face that looked hewn from one. He didn't greet them. He threw practice swords—real, sharp steel—at their feet.
"Your bond is a crutch,"he announced, his voice bouncing off the stone. "A safety net for the weak. True hunters rely on skill, discipline, and individual might. You will learn to fight as individuals first. Only then will you be permitted to practice as a pair."
The message was clear:the Dyad was a curiosity, but their unity was considered a weakness to be broken down and rebuilt under the kingdom's control.
The training was brutal. It wasn't about synergy; it was about survival. They were pitted against older wards of the kingdom—teenagers who had been training since they could walk. Erik, with his analytical mind, learned parries and footwork quickly, but was overpowered by sheer strength. Kaitlyn's raw power was wild, ungoverned; she'd win a bout with a shocking burst of force, then leave herself open and be floored by a precise strike.
They returned to their chambers each evening bruised, battered, and silently fuming. Jonas and Maria would meet them, their faces tight with a helpless rage.
"This is barbaric!"Jonas would snarl after the first week, confronting a placid Rhys in a hallway. "They're children! You're breaking them!"
"We are tempering them, Mr. Kelsey," Rhys replied calmly. "Steel is forged in fire and hammer blows. Would you have them remain soft iron?"
The hammer blows came daily. And the healer, Rebekah—"Becky" to her daughter—was always there afterwards. She was a small, quiet woman with kind eyes and hands that glowed with a cool, green-gold light. As she knit muscle and bone with a touch, she'd murmur apologies. "They push too hard, too fast. The old ways are… unforgiving." Her daughter, Mildred—"Mills"—a girl with her mother's kind eyes and a nervous smile, often helped, fetching salves and offering shy words of encouragement to Erik.
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The "school" was another shock. It was held in a vast library-chamber, and was less a school and more a tailored indoctrination. They were taught Hunter genealogy (placing the Dyad as a rare but natural outgrowth of certain pure bloodlines), Advanced Magical Theory (focused on combat applications), and the Glorious History of the Cŵn Annwn (a relentless saga of the kingdom's righteous control over the supernatural dark).
Their classmates were the kingdom's other wards and the prince himself.
Prince David was fifteen, with his father's wintery good looks and a crown of arrogance already settled on his brow. He was instantly, possessively fascinated by Kaitlyn. He saw her not as a person, but as the fiery, exotic half of a trophy. He'd commandeer her in strategy sessions, shower her with backhanded compliments. "For a wildling, you show… spark." His attempts to flirt were orders in disguise.
Arthur was different. A ward, like the others, but with a quiet, watchful intensity. He was David's age but seemed older, carrying a silent weight. He didn't speak to Kaitlyn; he observed her fights in the Crucible, and once, when she was staggering from a blow, he was the one who called for a halt, his voice cutting through Gareth's indifference. Afterwards, he simply handed her a waterskin. "Your defence on the left is predictable. He's exploiting it." His advice was practical, unadorned. Kaitlyn, who despised David's preening, found herself listening to Arthur.
Morgan, sharp and fiercely competitive, seemed to view the Dyad as a benchmark to surpass. She ignored Erik, focusing all her rivalry on Kaitlyn.
And then there was Mills. Shy, bookish Mills, who blushed when Erik thanked her for a healing salve. She started seeking him out in the library, showing him secret, softer texts on magical theory that her mother had access to, texts about bonds and empathy that were frowned upon by Gareth's philosophy. "They think the bond is just for sharing strength," she whispered one day, her finger tracing an illustration of intertwined light. "Mum says it's for sharing understanding. That's stronger."
Erik, starved for any knowledge that validated what he felt, found himself drawn to her. She was a refuge of quiet sense in the brutal, cold logic of the Citadel.
The social lines were drawn, and they were dangerous. David, noticing Kaitlyn's respect for Arthur, took to mocking and sabotaging the older boy at every turn—"mislaying" his gear, assigning him the worst duties. The malice was thinly veiled.
One evening, after a particularly gruelling session where Gareth had forced Erik and Kaitlyn to fight each other to "burn out your dependency," they lay on the floor of their cavern, aching and demoralised.
"This isn't working," Erik gasped, holding an ice-crystal pack to a swollen eye. "He's trying to separate us. And it's working. I couldn't feel you during that last bout. It was just noise and pain."
Kaitlyn, nursing a wrenched shoulder, nodded, her eyes bright with furious tears. "They're making us weaker. On purpose."
The door to their chamber slid open. It was Mills, looking nervous, with Arthur a silent shadow behind her.
"Becky sent more salve,"Mills said softly, placing a pot on a table. She hesitated, then looked at Erik. "There's a place. A old steam-vent chamber near the geothermal forges. The magic there is… chaotic. It messes with the citadel's scrying spells. If you wanted to… practice… without them watching."
Arthur met Kaitlyn's gaze. "A bond isn't a weapon you turn on and off. It's a stance. You can't find it fighting each other. You have to find it with each other. Away from the hammers."
It was a risk. Defiance. But the offer was a lifeline.
That night, deep in the forgotten, steaming heart of the mountain, Erik and Kaitlyn tried again. Not as individuals forced to clash, but as a dyad. They didn't spar. They moved in sync through the hot, misty air, matching breath to step, relearning the feel of their shared rhythm without Gareth's critical glare. It was clumsy, but it was theirs.
Watching from the entrance, Mills and Arthur kept lookout. A fragile, secret alliance was born in the citadel's shadow. But above, in the glittering royal chambers, Prince David seethed, jealous of a connection he could not command, and plotted to break what he could not possess.
The gilded cage was comfortable. The food was exquisite, the beds soft, the education elite. But the price was their very selves. And in the dark, with stolen salves and secret meetings, the Dyad and their new, precarious allies began the slow, dangerous work of learning how to pick the lock.