The walk back to my "home" took exactly four hundred and twelve steps. I counted every single one to keep my mind distracted from the biting frost.
The Umbra slums were a maze of narrow alleys, rusted pipes, and towering brick walls stained black with soot. The pale green Aether-fog clung to my ankles like heavy water. Every shadow looked like it was moving, and Arthur's memories warned me that sometimes, the shadows did move. Monsters called Aberrations hunted in the dark, feeding on the weak.
I finally reached a dead end behind a massive, ruined factory. Giant, rusted iron gears jutted out of the crumbling brickwork like broken bones. Tucked beneath a pile of rotting wooden planks was a small iron grate.
I moved the planks, pulled the heavy grate open, and slid down into the pitch-black hole.
I landed on a dirt floor with a soft thud. I quickly pulled the grate shut above me, plunging myself into total darkness. My hands fumbled against the cold dirt wall until my fingers brushed against a small box of matches and a cracked glass lantern.
I struck a match. The small, yellow flame was the most beautiful thing I had ever seen.
I lit the lantern, casting a weak, flickering light across my hideout. It was barely a room. It was an old maintenance cellar. The ceiling was so low I couldn't stand up straight. There was a thin, dirty mattress in the corner, a pile of stolen metallic junk Arthur had been collecting to sell, and a tin bucket for water.
It was pathetic. But it was safe.
I collapsed onto the mattress, my teeth chattering uncontrollably. I wrapped my arms around my chest, trying to preserve my core body temperature. I was so cold my fingers were turning blue.
I need heat, I thought, my breath puffing out in white clouds. If I don't get warm, Arthur's malnourished body is going to go into hypothermic shock.
I closed my eyes and thought about the Church Inquisitor in the street. I remembered how he had snapped his fingers and pulled thermal energy into his hand to create fire.
The Church called it "The Grace" of the Eye. They believed it was a holy gift. But I was a university science student. I knew that heat is just the transfer of kinetic energy between atoms. When molecules move fast, they get hot. When they slow down, they get cold.
If that Inquisitor can speed up the molecules in the air using his body, maybe I can do it too, I reasoned.
I didn't have a textbook to guide me, only the fuzzy, superstitious memories of a slum boy. According to Arthur's knowledge, "magic" came from the blood. You had to feel the heavy, violet blood pumping through your veins and push it outward.
I held my hands out in front of the lantern. They were shaking violently.
I closed my eyes and focused. I listened to the steady thump-thump of my heart. I pictured the metallic, violet blood flowing through my arms, down to my wrists, and into my fingertips. I imagined the atoms in the air vibrating, moving faster and faster, generating friction. Generating heat.
Come on, I gritted my teeth. Friction. Kinetic energy. Burn!
I felt a sudden, sharp pull in my chest. It felt like a vacuum had just opened up inside my ribs. A strange energy flowed from my heart, rushing down my arms.
I opened my eyes, expecting to see a spark. Expecting to feel warmth.
Instead, the weak yellow flame inside the glass lantern instantly died.
The room plunged into darkness. But it wasn't just dark. It was suddenly, violently, impossibly cold.
A sharp cracking sound echoed in the small cellar. I looked down. The tin bucket of water sitting two feet away from me had frozen solid in the blink of an eye. The thick layer of frost was rapidly spreading across the dirt floor, creeping up the walls, and crawling toward my boots.
I gasped, snatching my hands back.
As soon as I broke my concentration, the freezing phenomenon stopped.
I sat there in the pitch black, my heart hammering against my ribs. I couldn't see anything, but the air in the cellar was now so cold it burned my lungs.
What did I just do? my mind raced in a panic.
I didn't create heat. I didn't speed up the molecules. I did the exact opposite. I had forced the molecules in the room to come to an absolute, dead halt.
In chemistry, there are two types of reactions. Exothermic reactions release heat—like a fire. Endothermic reactions absorb heat from their surroundings, making everything around them freezing cold.
The Inquisitor was exothermic. He created order and energy.
I was endothermic. I was a walking black hole that sucked the heat out of the room.
Arthur's memories suddenly flared up in my mind, filling me with a deep, primal terror. The Church taught that the Eye in the Sky gave its believers "The Grace" of heat and light. But those who were born with the power of cold and decay were cursed. They were called "Heretics." They were the users of "The Rot."
If the Inquisitors found a person who could freeze water just by thinking about it, they wouldn't just kill them. They would drag them to the public square and burn them alive to cleanse their soul.
I stared into the dark cellar, trembling from the cold and the fear.
I wasn't just a poor orphan in a Victorian slum. I was public enemy number one. My very biology was a crime against their god. And I had no idea how to control it.
I shoved my freezing hands deep into the pockets of my oversized coat to warm them up.
My fingers brushed against something hard and heavy. It was a cold cylinder made of metal.
I frowned in the dark. I pulled the object out of my pocket. As soon as my skin gripped the metal, a faint, glowing blue light illuminated the cellar.
It was a brass tube, covered in jagged, glowing mathematical symbols.
I stared at it, Arthur's memories failing me. He had looted this from a dead aristocrat in the alley earlier tonight, just before I woke up in his body. He hadn't known what it was.
But looking closely at the glowing blue symbols, my university-trained eyes recognized something the people of this world had forgotten thousands of years ago.
It was an advanced algebraic equation. And it was missing a variable.