The summons came three weeks after the Serpent's Den.
Seiji had spent those weeks in a strange limbo — training by day, sitting with Mikoto in the clearing by evening, sleeping in the Senju compound at night. The rhythm felt almost normal, almost peaceful. But he knew it couldn't last. ANBU didn't allow for peace.
The masked messenger found him in the training yard, practicing his bone manipulation against a series of wooden posts. The messenger's mask was a hawk, its beak sharp and curved.
"Yoru no Osu. Report to Commander Hatake. Immediate deployment."
Seiji caught the scroll the messenger tossed and read it quickly. The words were brief, clinical, stripped of anything unnecessary.
Mission Classification: S-Rank
Objective: Intercept and eliminate Kumo envoy carrying orders for border incursion
Location: Land of Frost, northern mountain passes
Team: Wolf (Sakumo Hatake), Tiger, Owl, Nightingale, Yoru no Osu
Duration: Estimated ten days
Departure: 0600, North Gate
A team mission. His first since joining ANBU.
He had operated solo on the Serpent's Den, relying only on his own skills and judgment. This would be different. He would have to coordinate with others, trust others, rely on others. And they would have to trust him.
Tiger. Owl. Nightingale. Code names he had heard in passing but never worked with directly. Sakumo's core squad — the operatives he trusted most.
Seiji gathered his equipment and headed for the North Gate.
---
The team was already assembled when he arrived.
Five figures stood in the predawn darkness, their ANBU masks catching the faint light of the waning moon. Sakumo's wolf mask was unmistakable, its gray fur and sharp ears marking him as the White Fang. Beside him stood three others.
Tiger's mask was orange and black, striped like the predator it represented. The operative was tall, broad-shouldered, with the powerful build of someone who favored direct combat. A massive sword was sheathed across their back.
Owl's mask was white with large, circular eye holes that gave the impression of constant watchfulness. The operative was slender, shorter than the others, moving with an economy of motion that spoke of precision and speed.
Nightingale's mask was delicate, almost beautiful — a small bird with a long beak, painted in soft browns and creams. The operative was the smallest of the group, their frame suggesting either a woman or a very young man.
"Yoru no Osu," Sakumo said as Seiji approached. "You're the last to arrive. Good. We can begin."
"My apologies, Commander."
"No need. You're exactly on time." Sakumo's voice held a hint of warmth. "Team, this is Yoru no Osu. Night's Mercy. He's new to ANBU, but not to combat. I've worked with him personally. He's reliable."
Tiger's mask tilted. "The White Bone Baku. I've heard stories."
"They're exaggerated," Seiji said.
"Are they? I heard you killed thirteen operatives in a single night. Solo infiltration. No support."
"That part is accurate."
Tiger was silent for a moment. Then a low chuckle emerged from behind the mask. "I like him. He doesn't brag."
"Enough." Sakumo's voice cut through the banter. "Mission briefing. Listen carefully."
He unrolled a map on the ground, anchoring its corners with stones. The Land of Frost spread across the parchment — a narrow country wedged between Fire and Lightning, its terrain dominated by mountains and frozen rivers.
"The Kumo envoy departed from the border outpost three days ago. He's traveling with four guards, all chunin-level or higher. Their route takes them through the Shimogakure Pass — the only traversable route through the mountains this time of year."
"The pass is a death trap," Owl said. Their voice was androgynous, calm. "Avalanches. Crevasses. Temperatures that freeze chakra itself."
"Which is why they chose it. They're not expecting pursuit." Sakumo traced the route with his finger. "We'll intercept them here, at the narrowest point of the pass. The terrain will force them into single file. We eliminate the envoy, recover the orders, and withdraw. No survivors. No witnesses."
"Understood," the team said in unison.
"Nightingale, you're on reconnaissance. Your sensory range is the best among us. Tiger, you're our heavy combatant — you'll engage the guards directly. Owl, you'll provide ranged support and cover our withdrawal. Yoru no Osu, you're with me on the envoy. We take him together."
Seiji nodded. "The envoy's combat capabilities?"
"Unknown. He's a diplomat, not a frontline shinobi, but Kumo doesn't send anyone important without protection. Assume jonin-level abilities until proven otherwise."
"Understood."
Sakumo rolled up the map. "We move out in five. Check your equipment. Say your prayers if you're the praying type. This mission will test everything you've learned."
The team dispersed to make final preparations. Seiji checked his kunai, his bone armor's responsiveness, his chakra reserves. Everything was ready.
Tiger approached him as he adjusted his mask.
"First team mission?"
"Yes."
"I've been doing this for eight years." Tiger's voice was low, meant only for Seiji. "Sakumo doesn't bring new operatives into his core squad lightly. He must see something in you."
"I completed my first solo mission successfully."
"Thirteen kills. I heard." Tiger's mask tilted. "But killing isn't the same as working with a team. Out there, in the pass, we rely on each other. One mistake, one moment of hesitation, and people die. People you've come to know."
"I understand."
"Do you? Because I've seen new operatives freeze. I've seen them make choices that got their teammates killed. I've carried their bodies back from missions that should have been simple." Tiger's voice hardened. "Don't be one of those operatives. Don't make me carry your body home."
"I won't."
Tiger studied him for a long moment. Then they clapped him on the shoulder.
"Good. Let's go freeze our asses off in the mountains."
---
The journey to the Land of Frost took three days.
They traveled at ANBU pace — which meant fast, silent, and relentless. Eighteen hours of movement per day, broken by short rests and cold rations. Seiji's body was young but conditioned by years of war; he kept up without complaint.
The terrain changed gradually as they moved north. The green forests of Fire Country gave way to rocky highlands, then to sparse evergreens dusted with snow. The air grew thin and cold, each breath a small shock to the lungs.
Nightingale proved invaluable. Their sensory abilities extended far beyond normal range — they could detect chakra signatures from miles away, distinguishing between wildlife and human targets with uncanny precision.
"Deer herd, two miles east," Nightingale would report. "No human signatures within scanning range."
Owl was the team's navigator, reading the terrain with an expertise born of years operating in hostile environments. They found paths that didn't appear on any map, shortcuts that saved hours of travel time.
Tiger was the team's heart — loud, brash, constantly cracking jokes that seemed wildly inappropriate for ANBU operatives. But beneath the humor was steel. Seiji watched them train during rest periods, their massive sword moving in patterns that were both brutal and beautiful.
And Sakumo was Sakumo. Calm. Steady. The anchor that held the team together. He spoke little but observed everything, his gray eyes missing nothing.
On the second night, as they huddled around a small, smokeless fire, Nightingale spoke to Seiji directly for the first time.
"You're young."
"I'm eleven."
"I was twelve when I joined ANBU. Sixteen now." Nightingale's voice was soft, almost gentle. "The shadows age us faster than years."
"Does it get easier?"
"No. But you learn to carry it." Nightingale paused. "Sakumo says you chose the name 'Night's Mercy.' Why?"
Seiji thought of the golden threads he saw through his Tenseigan. The lives he had taken. The lives he had spared.
"Because mercy is a choice," he said. "Even in the darkness. Especially in the darkness."
Nightingale was silent for a long moment. Then, slowly, they nodded.
"I think I understand. I'm called Nightingale because I sing. Not for beauty — for function. My voice carries chakra that can calm or disrupt. It's not mercy. It's control." Their mask tilted toward Seiji. "Perhaps I should learn from you."
"Perhaps we can learn from each other."
Nightingale made a soft sound that might have been a laugh. "Perhaps we can."
---
The Shimogakure Pass appeared on the fourth morning.
It was a narrow gorge carved through the mountains by an ancient river, its walls sheer and ice-slicked. The wind howled through it like a living thing, carrying snow and the promise of death. Temperatures had dropped far below freezing; even with chakra regulation, Seiji felt the cold seeping into his bones.
"Beautiful," Owl murmured.
"Deadly," Tiger corrected.
"Both things can be true."
Sakumo raised his hand, and the team fell silent. "Nightingale. Report."
Nightingale closed their eyes behind the mask, their chakra extending outward in a sensory web. Minutes passed. The wind screamed.
"Five signatures. Four chunin-level, one significantly stronger. They're in the pass, approximately three miles ahead. Moving slowly — the terrain is difficult."
"The envoy," Sakumo confirmed. "Positions?"
"Single file. The strongest signature is in the center, protected by two guards ahead and two behind. They're being careful."
"They're being smart. But not smart enough." Sakumo turned to the team. "We move into position. Tiger, you'll take the rear guards. Owl, eliminate the forward guards from range. Nightingale, you're on overwatch — alert us to any changes. Yoru no Osu, with me on the envoy."
"And if the envoy is stronger than anticipated?" Seiji asked.
"Then we adapt. We always adapt."
They moved into the pass.
---
The cold was unlike anything Seiji had experienced.
His bone armor, usually a source of comfort and protection, felt brittle in the freezing air. His chakra regulation kept his core temperature stable, but his extremities — fingers, toes, the tips of his ears — burned with cold. Every breath was a knife in his lungs.
The team moved in perfect silence, their dark uniforms blending with the shadows of the gorge. Nightingale's sensory web guided them, warning of unstable ice and hidden crevasses. Owl found vantage points among the rocks, their keen eyes tracking the enemy's progress.
Seiji stayed close to Sakumo, watching the White Fang move through the frozen hellscape with practiced ease. Sakumo had done this before. Many times. The cold didn't seem to touch him.
How many missions has he survived? How many frozen passes, how many enemy strongholds, how many nights in the shadows?
And yet Sakumo was still human. Still kind. Still capable of love and mercy.
That's who I want to be, Seiji realized. Not a weapon that kills without feeling. A person who chooses mercy, even after everything.
The envoy's party came into view.
They were exactly as Nightingale had described — five figures in Kumo's white and gray, struggling through the deep snow in single file. The envoy was in the center, a tall man in heavier robes, his face hidden by a fur-lined hood. The guards flanked him, their chakra signatures alert but weary.
Sakumo raised his hand. The team froze.
"On my signal," he breathed. "Owl, take the forward guards. Tiger, the rear. Yoru no Osu, with me."
Seiji's heart hammered. His Tenseigan activated, showing him the golden threads of five lives pulsing in the white wilderness. Soon, those threads would fade.
This is what I do. This is who I am. A protector who kills.
Sakumo's hand dropped.
Owl moved first. Two arrows — no, two senbon, needle-thin and coated with something dark — flew from their position among the rocks. They struck the forward guards in the necks, so precisely that both men dropped without a sound.
Tiger erupted from the snow behind the rear guards. Their massive sword swept in a horizontal arc, and both guards fell, their bodies nearly severed.
The envoy turned, his hood falling back to reveal a face scarred by years of combat. His eyes widened — not with fear, but with recognition.
"White Fang," he hissed.
Sakumo and Seiji descended on him together.
The envoy was jonin-level, as Sakumo had predicted. Lightning chakra exploded around his fists as he defended himself, his strikes fast and brutal. But he was fighting two opponents, one of them legendary.
Sakumo's White Fang blade flashed, cutting through the envoy's lightning armor like paper. The envoy stumbled, off-balance. Seiji's Gravitic Pulse caught him mid-stumble and slammed him against the ice wall.
A bone spike through the heart ended it.
The pass fell silent. Five bodies lay in the snow, their golden threads fading. The mission was complete.
"Recover the orders," Sakumo said quietly. "Then we burn the bodies and withdraw."
Seiji knelt beside the envoy and searched his robes. The orders were in an inner pocket — a scroll sealed with Kumo's cloud symbol. He tucked it into his own pack.
"Got them."
"Good." Sakumo's voice was tired. "Let's go home."