The morning sun over Valtheris bled gold across the rooftops, but Eren barely noticed. His hand still tingled where the mark had appeared the night before — faint, glowing lines running down his forearm like living circuitry.
[Sync Anomaly: 1.2%]
[Warning: Unstable Data Link Detected.]
He'd seen the alert a dozen times since dawn, but no matter how many times he tried to scan it, the System refused to identify the source.
"Unstable, huh?" he muttered, flexing his hand. "Guess that makes two of us."
The shard he'd taken from the dungeon pulsed faintly in his pouch, like a heartbeat that wasn't his. Every time he touched it, a faint whisper brushed his thoughts — a voice that sounded achingly familiar.
"…Eren…"
He froze mid-step in the crowded marketplace. The sound wasn't in his ears — it was inside his mind.
"Who's there?" he whispered.
No response. Just the hum of life around him — merchants shouting prices, the ring of hammers from the blacksmith's yard, the smell of fresh bread and smoke.
But deep down, he knew that voice.
Riel.
The name alone made his pulse quicken. He hadn't said it out loud in years — not since the day his brother vanished.
He shook his head, forcing the thought away. "Get it together. You're hearing things."
Still, the mark on his arm burned faintly in answer, and the shard pulsed once, as if laughing at him.
---
Far away, in a quiet room beneath the orphanage ruins, Riel sat cross-legged, surrounded by threads of light only he could see. Each thread vibrated softly, connecting to something unseen — people, places, maybe even worlds.
His fingertips glided across one thread — the brightest, the most alive. It throbbed gently in his palm, and every pulse sent warmth through his chest.
"Eren…" he whispered.
At the sound, the thread brightened, and for an instant, he saw flashes not his own — a busy city, a guild hall, a face looking down at glowing runes. His brother's face.
He gasped and pulled back. The vision faded, leaving only silence.
[System Message: Link Stabilized — 14%]
[Warning: Overuse may cause Desync.]
"Desync?" he murmured. "So… if I push too far…"
The journal beside him flipped open on its own. Strange glyphs bled across the page — warnings, fragments of code, symbols of the Bound and Unbound.
He read them aloud softly:
> "Two halves of the same code cannot exist apart. When the Link strengthens, so does the rift."
He swallowed hard. "So finding him might… destroy something else?"
Still, deep in his heart, he felt the tug — the call between brothers that no logic could silence.
He clenched his fist. "No matter what it costs, I'll find you."
The threads shivered in answer.
---
Meanwhile, Eren stood before the Adventurer's Guild board, staring at the newest postings. His group from the last raid had split — some to heal, some to celebrate — but he couldn't rest.
Every quest title blurred together until one caught his eye:
[High-Risk Quest: Investigate Rift Activity — West Outskirts]
Reward: 300 gold | Rare Item | System Access Key
Rift Activity.
The word sent a chill through him. The same strange energy that had leaked from the dungeon core… and now spreading near the city.
He accepted the quest instantly.
As he turned to leave, Kairn, the spiked-armored adventurer from before, called out to him. "Hey, rookie! Going solo again?"
Eren shrugged. "Just a quick job."
Kairn snorted. "You're either brave or suicidal. Either way, you're guild material."
Eren smiled faintly but didn't reply. He couldn't explain it — the drive inside him wasn't just ambition anymore. It was instinct. The need to move, to follow the pull inside his veins.
By dusk, he reached the outskirts — a field of broken pillars and warped space that shimmered like heat haze. His System flared with warnings.
[Spatial Distortion Detected.]
[Origin: Unidentified External System — "Unbound."]
Eren's eyes widened. "Unbound?"
Before he could react, the mark on his arm blazed to life.
Across the worlds, Riel felt it too.
Both brothers gasped as the Link surged — a current of shared memories, sensations, emotions flooding between them. Riel saw flashes of Eren's fight, his exhaustion, his loneliness. Eren felt Riel's fear, his awakening, the echo of the word Unbound.
For a heartbeat, their voices overlapped.
"Riel?"
"Eren?"
Then the connection spiked.
[Warning: Sync Level Exceeded — Emergency Split Initiated.]
Light erupted from both of them, tearing the world apart in twin flashes.
When the glow faded, Riel was left gasping in the ruins — and Eren stood in the center of the rift field, facing a figure made entirely of shadow.
Its voice rasped like grinding metal. "Found you… Fragment of the Unbound."
Eren drew his sword, heart pounding. "If you want him," he said through clenched teeth, "you'll have to go through me."
The shadow's red eyes glowed brighter. "So be it."
As the sky above split open, the brothers' destinies pulled tighter — a bond stronger than the worlds that tried to divide them.
---