Lumina Brightstone's Arc

Chapter 3 of 3

Lumina reached the narrow gap and knew the plan was breaking. The river trolls stood in the throat of land, blades out, but nothing stood between them and the machines. No wall. No stakes. Just wet ground and bare rock. The grinding machines rolled closer, and their treads chewed the earth. The river trolls could not stop steel with their bodies alone. Lumina saw it clearly. They would be crushed, and the whole flanking plan would die with them. "Where is the barricade?" she shouted. The river troll with the waist-long braid turned. "We had no time to build one. They came faster than the horn." Thalgrim appeared beside Lumina, moving slow through the ferns. He did not seem to rush, yet he was there when she needed him. He studied the machines, then the ground, then a slow shape at the edge of the gap. "You are looking for a wall," he said. "You already have one." Lumina followed his gaze. A great tortoise sat in the mud, its shell taller than a troll. Moss covered its back in a thick green mat. Its head and legs were bright pink and purple, and it chewed slowly, ignoring the noise. Lumina had seen the beast graze the gap for years. She had never thought of it as anything but slow. "That will not move for us," she said. "It moves toward the blue light," Thalgrim said. "It always has." He pointed with one thick finger. Along the ridge wall grew a panel of clustered mushrooms, glowing bright blue in the dark. Small beetles crawled among the caps, their backs shimmering with the same blue shine. Lumina understood. She scraped a hand across the fungal panel and tore loose a clump of glowing caps. Beetles scattered up her arm. She held the light low, in front of the tortoise's head, then walked backward into the mouth of the gap. The tortoise lifted its bright head. It took one step. Then another. It followed the glow across the throat of land, until its huge mossy shell filled the narrowest point. "Now brace it," Lumina called. The river trolls jammed rocks and logs against the beast's legs and sides. The tortoise settled, chewing, and did not fight them. Its shell made a wall of living stone across the gap. The first machine hit it. The tortoise did not break. Metal shrieked and treads spun, but the beast held, and the enemy jammed against it. The machines could not turn in the narrow ground. They ground against each other, stuck in a heap of their own steel. Lumina climbed the ridge and raised her horn. The trap was set now, not by a wall, but by a beast no one had valued. She blew, and the chieftain's fighters poured down onto the stalled machines. The gap held. But she saw the enemy's rear ranks halt and turn, already reaching for the ridge behind her fighters.