The bunkhouse room on the fourth floor of the commoner barracks was eight paces wide by five paces deep. He smelled of damp wool, animal fat soap. The greasy iron dust that drifted continuously from the foundry chimney pipes three streets away.
In the corner beneath the leaking window frame, Toby Mallow was experiencing a quiet, arithmetic seizure.
Toby sat cross-legged on his straw mattress. It was surrounded by four columns of brass-stamped Vanguard copper tokens, a small stack of blue five-credit vouchers, and his open double-entry ledger. His solar metal pen flickered wildly as he scratched numbers into the margins, his glasses pushed up onto his sweaty forehead. For an hour, he had checked the totals against his receipts, unable to believe that their pockets were no longer fully empty.
“Five hundred and sixty credits,” Toby muttered, his voice trembling with respectful dread. “Minus five credits for the bursar’s registration stamp. Minus twelve credits for the broken window latch in November. That leaves five hundred and forty-three. If we ration the beans... If Barnaby eats only discarded cabbage stalks from the lower wholesale market...”
Toby had grown up behind the flour barrels of his family’s bakery in District 9. House Vance’s town grain trade ring imposed a forty percent tax on imported wheat. Then, his father’s shop went into receivership. That forced Toby to enter the academy on an indentured supply boss scholarship. Every copper spent was an open wound to his nervous system. He could calculate compound interest in his head faster than an academy clerk. He treated every receipt like a sacred treaty.
Beneath Toby’s cot, a massive mound of grayish-pink flesh shifted with a deep, liquid snort. Barnaby, Toby’s three-hundred-pound Spotted Burrow-Hog, opened one cloudy brown eye from his nest of old burlap sacks, sniffed the air, decided there was no immediate danger of exercise. Then he returned to snoring at a hum that rattled the windowpanes. Barnaby had been purchased from a butcher’s cart two years ago. Just then, he was no larger than a melon, and despite living entirely on kitchen scraps and potato peelings, he had developed a layer of underground blubber that rendered him fully immune to drafty winters. With an idle flick of his flat, rubbery snout, the hog nudged the cast-iron draft damper on the stove shut, preserving the heat like an expert fire tender.
Arthur stood by the cast-iron potbellied stove in the center of the room.
Over the glowing coal grate, a heavy iron pot simmered with three liters of water, two pounds of crushed beef soup-bones scavenged from the butcher shop district, a handful of dried bitter-clover, and thirty grams of powdered iron-melted rock waste from the upkeep bins. The steam rising from the brew smelled rich, salty, and distinctly metal.
Beside the stove, Grimm lay stretched out on the bare floorboards.
The transformation had settled into the hound’s cellular structure over the past four hours. But the body-energy cost was visible. Grimm’s flanks were hollow, his breathing deep and slow. Every few minutes, a faint, muscular twitch rippled through his left hind leg—the natural nervous aftershock of bone rebuilding.
Arthur knelt beside the dog. He carried a chipped baked-clay bowl filled with lukewarm broth and softened bone marrow.
“Eat,” Arthur said gently.
Grimm cracked open his golden eyes. He didn’t lunge at the bowl like a feral stray. He raised his heavy head, sniffed the broth with cold and exact deliberation. Then began to lap the liquid with rhythmic, steady strokes of his broad tongue. Within forty seconds, the bowl was polished cleaner than the day it was fired in the kiln.
Grimm let out a low, bass chuff of satisfaction, lowered his head. Then he rested his chin directly across Arthur’s left boot.
The hound’s weight was substantial—nearly fifty pounds of dense, carbon-heavy muscle and bone. Through the leather of his boot, Arthur could feel the rhythmic pulse of Grimm’s main thigh blood vessel, steady and slow at forty-five beats per minute.
“Look at him,” Toby whispered. He lowered his ledger and peering over the edge of the mattress. “Arthur, he looks like a demon from the Outer Rift trenches. His teeth... When he cracked Julian’s drake, it sounded like a rail-car jumping the tracks. Are you sure he won’t snap in the middle of the night and chew off my shins?”
“Grimm’s jaw has a bite force of twenty-four hundred pounds of pressure,” Arthur said, stirring the leftover broth with a wooden spoon. “If he wanted to chew off your shins, Toby, he wouldn’t do it in the middle of the night. He would do it while looking you straight in the eye.”
Toby swallowed audibly and pulled his feet six inches further onto the mattress.
“That doesn’t comfort me, Arthur. Not even a little bit.”
Arthur smiled faintly, looking down at his worn boots. “He won’t touch you. You’re part of the ledger now. But more importantly, we need to understand how his metabolism is processing that catalytic iron. The jet-black bone honeycomb lattice isn’t just passive bone. It’s a pressure-sparking matrix. Every time his paws strike the floor, the clockwork stress generates a micro-voltage that stimulates osteoblastic rebuilding. If we don’t supply bio-available sulfur and calcium, his marrow will pull minerals from his own teeth.”
Arthur set the wooden spoon down and sat back against the wall, stretching his tired legs. “How much did you say the bone meal costs at the town grain store?”
“Sixteen coppers a pound for grade-three agricultural sweepings,” Toby said, instantly shifting into his comfort zone. He tapped the ledger with his metal pen. “Thirty-two coppers for steamed marrow meal from the slaughter pens. If Grimm eats three pounds a day to maintain that bone thickness, that’s nearly fifteen credits a month just to keep him from absorbing his own skeleton. Plus Barnaby’s mash. Plus our tea. And don’t forget the corporate monopolies—ApexBio just bought out the western feed mills. It means non-patented bone meal prices will jump twenty percent by next Tuesday. They want every independent tamer in the lower wards bankrupt or indentured to their contract labor divisions.”
Toby groaned and pressed his forehead against the open ledger.
“We’re going to starve, Arthur. We won the arena match, we saved your family name. We’re still going to be begging for potato skins by midwinter. My father always warned me: you can fight a landlord. But you can’t fight a grain cartel.”
A soft, metal rattle broke the quiet.
Arthur looked toward the corner. While Toby was lamenting their financial doom, Grimm had quietly stood up, padded across the floorboards without a sound. Then they nudged the bottom shelf of the pantry cabinet with his black snout.
On the shelf sat a small tin of roasted sunflower seeds that Toby had saved for his evening snack.
With extraordinary delicacy for a beast with high-pressure jaws, Grimm grasped the rim of the tin with his front incisors. Then he lifted it down. But he turned to carry his prize back to the rug. Then, his rear hip bumped the wooden leg of the washstand.
The washbasin rattled. Toby’s head snapped up.
“Hey! My seeds!” Toby squawked.
Grimm froze mid-step. The tin of sunflower seeds remained clamped gently between his teeth. His golden eyes darted toward Arthur, who was watching him with raised eyebrows.
Without making a sound, Grimm lowered his head. It set the tin carefully back onto the floor, and turned around.
He didn’t tuck his tail between his legs. He didn’t whimper. Instead, the fifty-two-pound apex hunting beast walked directly over to the narrow ninety-degree corner between the brick chimney and the outer wall. He pressed his broad black nose firmly into the plaster corner, lowered his head, and stood fully rigid. He stared at the blank brickwork.
Silence settled over the room.
Toby blinked, his glasses slipping down his nose again. “What... What’s he doing?”
“He’s in the corner,” Arthur said, fighting a sudden twitch at the corner of his lips.
“I can see he’s in the corner. Why is he standing like a coat rack?”
“Hungry mental shifted weight,” Arthur said, his tone entirely serious. “In his mind, if his eyes are buried in a ninety-degree angle and he can’t see us, then we can’t see him either. It’s a behavioral shame response common in highly territorial canines after a boundary rule-break.”
Toby stared at the massive black wolf-hound, whose tail gave a single, hesitant, tiny twitch against his flank.
“He thinks he’s invisible?” Toby asked.
“Fully invisible,” Arthur confirmed.
Toby let out a breathless, half-strangled laugh. It shook his head as he picked up the tin from the floor. He popped three sunflower seeds into his mouth and tossed two onto the rug behind the dog.
“You’re an idiot, mutt,” Toby muttered, though the fear in his voice had entirely evaporated. “Come on. If you’re going to eat seeds, at least chew them properly.”
Grimm didn’t move for ten seconds, maintaining his dignified invisibility. Then, with painful slowness, his left ear swiveled backward toward the seeds. He backed out of the corner with measured, silent strides, vacuumed the seeds off the rug with his tongue, and right away resumed his position lying across Arthur’s boots.
Arthur reached down, resting his hand against the dog’s warm, solid ribs.
In the quiet room, a faint, amber line of test tracking data flickered briefly behind Arthur’s eyes. It confirmed what his fingers already knew:
Balance index: 94.2%. Synaptic latency: 3.8 split seconds.
The foundation was laid. Tomorrow, the real work would begin.