The pale foot settled on the stone without making a sound. Five long toes spread across the cracks while a narrow body pushed through the torn white membrane behind it.
A low vibration passed through the walls as the membrane peeled away from its shoulders.
HUM!
Kael felt the sound through his boots, but the chamber swallowed it before it could echo. Coughs, scrapes, and frightened whispers died close to the people who made them.
Jaro pressed his back against the wall. A loose strip from his bloodied palm caught on broken white glass, and Vaela pulled him free before the cut reopened.
"Keep your hands against your chest," she said while tightening the cloth. "I have enough wounds to watch without you opening both palms again."
"I was trying to get away from it." Jaro stared past her shoulder, unable to hide the tremor in his voice. "Nothing that large should be able to enter a room so quietly."
The new body straightened. A white shell covered its face, with shallow dents where eyes and a mouth should have been. No pulse moved in its long throat, while curved ribs opened and closed around an empty chest.
Mirrored plates at its shoulders, elbows, knees, and spine turned whenever Kael shifted. Three followed his bleeding wrist when it moved half an inch.
Renn kept his burned palm around the next survivor’s wrist and lowered his head to spare his injured throat.
"Look at the floor and keep touching the person beside you," he told the line. "All fourteen are here, and I need every hand to stay where I can count it."
The pale body’s head turned toward him.
A cord no thicker than a thread slipped between two ribs. It crossed the chamber and stopped a finger’s width from Renn’s lips. Kael stepped toward it, and the cord withdrew before his foot landed.
Jaro swallowed so hard the sound broke through the quiet.
GULP!
"I saw drawings of this below," he whispered. "The crews called the judgment a Null Verdict and the thing it built a Null Body. It appears after the earlier traps fail."
Vaela stayed beside him, one hand resting near the wrapped white edge at her waist. "Tell us what the drawings showed, and leave out whatever the crews only guessed."
Jaro rubbed his thumb against the wet cloth. "It watches how someone survives and changes the next attack. A man carried through one chamber lost every hand that reached for him in the next. Another broke an anchor, so the following body hid every anchor from him."
Renn glanced at the cord waiting near his mouth. "It saw me keeping the count, so it knows the others follow my voice."
"It knows your voice matters," Jaro said. "I do not think it knows why yet."
Kael waited for the Sovereign Root to respond. No alert crossed his sight, and no shard entered his body. Learning the name had not put him under hostile pressure, so his reserve remained at zero.
The masked face turned toward Jaro.
Three lines crossed the floor, joining Jaro to Kael, Kael to Renn, and Orrek’s injured shoulder to the nearest survivor. Each line brightened when someone looked toward the person at its other end.
Vaela followed the light with her eyes. "It is watching who protects whom. Keep moving your attention, even if your feet stay still."
Jaro looked sick. "The old drawings showed the same lines around guards, prisoners, and anyone carrying the wounded. It strikes the weaker body when protection makes the stronger one easy to predict."
Orrek shifted his chain into his uninjured hand. His injured shoulder remained low, but the line beneath it brightened anyway. "If it knows this arm hurts, I would prefer to disappoint it before it becomes confident."
The boy beside the furnace-scar woman wrinkled his nose. "It should watch both arms. You smell like old boot soup everywhere."
Orrek stared at him. A laugh escaped someone near the rear, followed by another from a woman who tried to hide it behind her wrist. Even Renn’s mouth twitched.
The line under Orrek’s boots flickered and lost its straight edge. The pale body turned its mask from the boy to Orrek and back again, unable to decide whether the insult meant fear, affection, or disobedience.
"Keep speaking like yourselves," Vaela said. "It understands simple reactions faster than people."
Orrek gave the boy a wounded look. "You may insult me again after we survive, but I expect a better recipe."
The pale body raised its left hand. Its fingers opened into five plates showing Kael pulling an anchor, breaking a pylon, holding a stair, crushing a crown, and carrying the injured.
All five fingers closed around the images. The fist pointed past Kael toward the living chain.
Stone began sliding from both sides of the corridor behind them.
SCRAPE!
Renn dropped to one knee and slapped his burned palm against the floor. Pain twisted his face, but his voice remained clear enough for the people nearest him to carry it backward.
"Get low and pull close to whoever you are holding. Do not try to make the line neat."
The survivors folded together. A worker fell, another cursed when a heel struck his shin, and the furnace-scar woman dragged the boy beneath her arm until the walls could find no straight gap between them.
A stone tooth struck the floor where a neck would have been.
CRACK!
Rock jumped across their backs. The rear four stayed connected to Renn by hands, sleeves, and one grip around an ankle.
Kael crossed the glowing line between himself and Renn. He dragged his wounded wrist through the line leading to Jaro and stopped in a place that made no sense for an immediate attack. The mirrored joints turned after him, lost the angle, and corrected twice.
The mask tilted.
Vaela stepped around a fallen survivor and caught the person’s shoulder before they rolled into the wall. "It expected Kael to move directly between the danger and the group. He chose a worse position, and now it has to reconsider him."
"The pause will not last," Jaro said. He pushed himself away from the glass and kept both bandaged hands against his chest. "Its joints are already changing."
Kael watched the ribs open wider. Darkness gathered inside the hollow chest while the plates along its spine locked into a new arrangement. The thing had not struck him, so the Root remained silent.
The empty ribs tightened around a gathering vibration.
HUM!
Kael changed his stance before the mirrored joints finished turning. "Move through the opening, but do not settle into an order it can learn. Keep all fourteen together."
They entered the corridor in an uneven knot. Renn stayed near the middle, using touch instead of shouting while his throat burned. Orrek moved along the outer side with his chain ready, and Vaela kept the most injured people away from the narrowest wall.
The passage forced everyone close. One side allowed room for the injured, while the other narrowed around shoulders and elbows. Their usual formation would repeat exactly what the pale body had watched before.
Vaela studied the changing width as she walked. "It wants us to choose the same protectors for the same people. We can change places without abandoning anyone, but injured bodies still need room."
Renn coughed into his wrist.
COUGH!
"I can pass the count by touch," he said when he had his breath again. "Anyone who feels two squeezes sends one squeeze backward. I will still know where the line breaks without giving it the same sound."
Jaro moved beside him, close enough to help but careful not to touch Renn’s damaged hand. "The crews tried silence in the drawings, and the rooms learned silence too. Changing the signal may buy more time than hiding it."
Orrek eased his chain around a corner before his shoulder followed. "I can change sides whenever the passage widens. My arm will complain, but it complains when I sleep, so the room will have trouble learning anything useful from it."
Their frightened instructions and exhausted jokes overlapped while the wall seams flashed at different moments and failed to hold one pattern.
The Null Body followed at walking speed. Its joints copied movement while the cords between its ribs measured who stayed connected, and the narrowing corridor tried to force every protector back into a familiar place.
Kael gave it his back for two steps. The seams brightened as it prepared for him to keep guarding the way ahead.
He turned on the third.
The mirrored plates snapped toward him a moment too late. The body stopped with one foot raised, and its balance shifted toward the wall before it recovered.
Vaela saw the failure. Her fingers closed around the wrapped white edge, though she did not draw it. "It predicts duty better than sudden anger. Keep making choices for people, but stop giving it the same shape."
The mask turned toward her. A thin line reached from its face to the wrapped object at her waist, remembering how she had cut the earlier white seams.
Vaela moved into a crooked corner where any clean strike would have to pass Kael, Jaro, and two jutting stones. She smiled with the tired impatience of a healer interrupted too often.
Jaro watched the line tremble. "It cannot decide whether you are treating someone or preparing to cut it."
"I would like to keep both options," Vaela said. "Everyone else should continue moving while it wastes time on me."
The Null Body lifted one plate-covered hand. Its shoulder joint opened.
CLICK!
The long arm drew back without another sound.
Kael saw the strike forming between Renn and the boy.