Britta Stonefoot pressed her ear to the cracked seal and heard something breathe. She was ten years old, small even for a dwarf, and she had spent all winter finding the tunnels the grown-ups had walled off in Icefang. She wanted to map every one. This was the first seal she had ever broken. Now, past the gap in the stone, the dark breathed back at her, slow and wet, and she had no light to see it. Her torch had died an hour ago. She had traded it, along with her boots, to reach this deep. She dug through her pack and found nothing that would burn. The breathing came again, closer, a sound like a bellows filling. "Don't go in there alone," a voice said behind her. Britta spun. Trikar Sporebeard filled the tunnel, so tall his three mushroom heads bent under the low ceiling. He was the only friend who came with her past the walls the adults built. His arms were thick as roof beams. Two of his faces frowned. The third, small and shy, smiled at her anyway. "You followed me," Britta said. "You left the Witch Shack door swinging." Trikar swung a sack off his shoulder. "You took her things." Britta had. She had crept into the crooked shack with its dripping candles and grabbed what she could. She pulled it out now: a pink bow, glowing soft, and one matching arrow that shone like a lit coal. Light poured from the arrow and filled the tunnel. The breathing stopped. In the pink glow Britta saw it. Past the seal crouched a beast of pale roots and gray fur, eyeless, its wide mouth open to taste the air. It flinched from the light and hissed. "Back up," Trikar said. All three heads watched now. Britta did not back up. She wanted to see what waited here. She had wanted it all winter. She raised the bow, nocked the glowing arrow, and aimed at the ceiling above the beast. Her hands shook. She let go. The arrow struck the stone and burst. Pink light flooded everything. The beast screamed and threw itself backward into the dark, deeper than her eyes could follow. Loose rock rained down where the arrow had hit. The whole cracked seal groaned and slid. "Run!" Trikar grabbed her arm and pulled. Stone crashed behind them. When the dust cleared, Britta turned back. The seal was gone. The gap she had opened was a wide, black mouth now, twice as tall. The beast was somewhere inside it. And the fresh light was gone too; her only arrow lay buried under the rubble. Britta stood in the dark and breathed hard. She had wanted to open the tunnel. Now it was open wide, the thing inside was awake, and she had no arrow left to light her way in. "We should tell someone," Trikar said. "No," Britta said. "We should go deeper."

The dust settled, and Britta heard the beast again. It moved out where the seal used to be, no longer trapped behind stone. Its wide mouth clicked as it tasted the air. It could not see her. But it could hear her. One scrape of her heel would bring it running. She pressed her back to the cold wall and held her breath. "Stop moving," Trikar whispered. All three of his heads went still. "It hunts by sound. We wait." But waiting was not a map. Britta needed to know how far the passage ran. She slid one bare foot forward. A pebble rolled. The beast's head snapped toward the noise, and it lunged, jaws wide, straight at the sound. A green shape stepped out of the dark and caught the beast mid-air. Britta had met this stranger only once, at the crooked house shaped like a giant pickle jar, where bacon hung in the windows and claw marks scarred the fridge. Brinley Picklesworth had thrown her out then, tail thumping, too busy for a small dwarf's questions. Now that same spiked tail swung hard and knocked the beast into the wall. Brinley planted their lady legs wide, red cape flat against their back, and glared with their one eye. "Wrong tunnel to be quiet in," Brinley said. "This one carries every sound. I followed you both from the noise you made an hour ago." The beast shook itself and turned toward Brinley's voice. It charged. Brinley did not run. They braced both muscled arms and shoved, driving the pale thing back toward the open passage. "It won't die," Brinley said. "But it will chase noise. Give it noise it can't reach." Britta understood. She grabbed a fist-sized rock. She threw it hard down the far tunnel, into the deepest dark. The rock clattered and bounced, loud and rolling. The beast froze, then bolted after the sound, claws scraping stone. Its steps faded down the black throat of the passage. Then Brinley's tail swung once more, not at the beast, but at the cracked ceiling above the tunnel mouth. Spikes bit rock. Stone groaned and dropped. A slab crashed down and sealed the far passage where the beast had run. The clatter stopped. The breathing was gone, walled off in the deep. Britta stared at the fresh rockfall. She had opened one seal. Now a new one blocked her path, and the beast was trapped behind it with the tunnels she had come to map. "You sealed it," Britta said. "Now I can't go through." "I sealed the beast," Brinley said. "Not you. There's another way down. I've seen it." They pointed their tail at a low crack in the side wall, no taller than Britta herself. Trikar bent to look. "Smells like old rot down there," he said. "Wrong. Like something cut." Britta was already on her knees, peering into the crack. The beast was behind her now. The map waited ahead.

Britta pushed her head into the crack. Cold air breathed out at her. She wriggled her shoulders past the first bulge of stone. Then her pack caught. The buckles snagged on both sides, wedging her tight. She twisted. The rock held her fast. Dark stretched ahead, and behind her the passage was silent. She could not go forward. She could not pull back. Her heart slammed against the floor. "Trikar," she said. Her voice came out thin. "I'm stuck." His three heads pressed close to the crack. "Don't jerk," one head said. "You'll pin your arm. Then we can't reach it." But his fingers were too thick to fit past her. He pulled at her ankle. She only slid an inch, then stopped harder. A new voice came from the tunnel behind them. "Stop tugging. You'll break her." An old woman stepped out of the dark. She was hunched, with long legs and long ropes of gray hair. Beads clicked at her throat. Britta had seen her once, giving orders to the flat sea outside a corn-covered outhouse, where she guarded the shore alone. Everyone said she was mad. No one went near her. "I called 53 tides," the woman said. "I know a body that's wedged wrong. Girl. What holds you?" "My pack," Britta gasped. "The buckles." "Then lose the pack." Marlena knelt at the crack. Her long arm reached past Britta's shoulder into the dark. Her fingers found the strap across Britta's chest. "I can reach one buckle. Not both. You reach the other." Britta's map was in that pack. Every tunnel she had drawn. She had come so far to fill those pages. If she dropped it in the crack, it fell into the black below. "Choose," Marlena said. "The pack or the dark. I've watched the sea take slower things than you." Britta found the buckle at her hip. She thought of the beast sealed behind her, and the tunnels still unmapped ahead. She could draw a new map. She could not draw one dead. She snapped the buckle open. Marlena pulled hers free at the same moment. The pack dropped away. It clattered down the crack and vanished into the black gap below. Britta shot forward, free, sliding onto cold flat stone. She lay there, breathing hard, safe on the far side. Marlena's face filled the crack behind her. "You're through," she said. "You're lighter now. Good. Down here, light things live." Britta sat up in the dark. Her hands were empty. No pack. No map. No food, no rope, no charts. Ahead, the passage ran on into deeper black, unmapped, waiting. She had wanted to map every sealed tunnel in Icefang. Now she stood inside a new one, with nothing to draw on and no way back through the crack.

Britta sat on the cold stone with empty hands. Her pack was gone. Trikar was gone, sealed behind the crack with his food and his rope and his stolen light. She could call him. But her voice would carry down the black passage ahead, and she did not know what waited there. She rubbed her palms together and made herself think. A faint glow leaked from deeper in the tunnel. She crept toward it. The light came from a plant. Thick vines climbed the wall, and tiny gnome heads grew along them like fruit. Each head wore a pointed cap that shone a soft blue, red, or yellow. The heads turned to watch her. They grinned. A cluster of them giggled, high and sharp, and the sound skipped down the passage. Britta froze. Something ahead answered. A wet, heavy shifting, like a body dragging over stone. She pressed flat against the wall. A huge flower swung into the glow. Its head split open into a wide mouth ringed with teeth. Purple petals framed the jaws. It had no eyes. It swayed toward the giggling gnome heads, hunting the sound, exactly the way the sound-beast had hunted her before. Britta understood. The gnome heads made noise. The flower chased noise. If it followed the noise, it would not follow her. But it swayed closer to her too, drawn by her breathing. She had to make the plant louder than herself. She reached for the vine and gripped it. Thorns bit her palm. She hissed and squeezed anyway, then shook the whole vine hard. The gnome heads shrieked with laughter, all of them at once. The flower snapped toward them. Its jaws crashed down on the vine and tore a mouthful of shouting heads free. It chewed. The other heads screamed louder. The flower lunged again, deeper into the tangle, dragging its stalk away from Britta and into the wall of vines. She ran. She scrambled past the feeding flower while it thrashed in the leaves. Her bleeding hand slapped the stone as she went. The passage bent, then opened into a wider space, and the giggling faded behind her. She stopped, gasping. Ahead, water dripped somewhere in the dark. New tunnels branched off in three directions. She had crossed to the far side alone, and she had lived. But she had no map now. No charcoal. No paper. She looked at her cut palm, wet and dark. She pressed one finger into the blood and drew a short line on the wall. Then a fork, three branches, the way she had come. It was ugly. It would stay. Britta stood in the unmapped dark, marking the stone with her own blood, and started forward into the branching tunnels.

Britta pressed her cut palm to the wall and drew another line. Her blood smelled sharp in the cold air. Then she heard it. Down the left tunnel, something breathed. Slow. Wet. It dragged closer, and each breath came faster, as if it had caught a scent. Her scent. She backed against the stone. Both other tunnels were too far. She had nowhere to run. A square shape stepped out of the right tunnel. It walked on human legs in red sneakers. It was a toilet, with a striped cap and green slime dripping from its mouth. Its brown eyes fixed on her. Britta did not scream only because her throat closed up. "You're bleeding," the toilet said. His voice was flat and plain. "That's what it smells. Blood comes up the pipes too. Then the thing that isn't happy follows it." "What are you?" Britta whispered. "Flush Gordon. I follow the pipes." He tilted his tank toward the left tunnel. The breathing was louder now. "That one's close. You can't outrun it. You have to drop the ceiling on it." "I can't. I have no light. No tools." Britta's hands were empty and shaking. Flush reached into his bowl. He pulled out a bow and an arrow, both pink and glowing with a soft light. Water dripped off them. "Came up last night. From below. I kept it." He held them out. "You know how these work?" Britta stared. She had fired a glowing arrow once, at a ceiling, and it had brought the stone down. "Yes," she said. "I've done it." She took the bow. It was lighter than the last one. The breathing turned into a low growl. Something pale filled the mouth of the left tunnel, tall and wet, its head scraping the roof. It had no eyes. It swung toward the smell of her blood. "Aim up," Flush said. "Where the crack runs." He pointed one finger at a dark seam in the ceiling above the tunnel mouth. Britta set the arrow. She pulled the string back to her ear. Her cut palm burned on the grip. The beast lunged. She let go. The arrow flew straight and struck the seam. Pink light burst across the stone. A crack split the roof with a snap. Then the whole ceiling of the left tunnel came down. Rock crashed onto the beast. It shrieked once and vanished under the pile. Dust rolled over Britta and stung her eyes. When the dust settled, the left tunnel was gone. A wall of broken stone sealed it shut. The breathing had stopped. Britta lowered the bow. Two tunnels remained now, not three. She looked at her blood line on the wall. It marked a fork that no longer existed. "You sealed it," Flush said. He picked a wet wipe off his arm and flicked it away. "Now you're stuck on this side too."