When the voice ceased, the room continued to shake with a low-frequency, nauseating hum from the dam’s massive turbines. Marry was looking at the trembling needle gauges in panic. "Sir, the main valve is locked! The killer has put the system into a 'feedback loop'. It’s not letting the mana out; it’s accumulating inside. The pressure is at a critical threshold; an explosion is inevitable!"

  "There is no such thing as inevitable, Marry," Eren said, leaning his steam-mace against his shoulder. "There is only a poorly timed mechanism."

  Eren leaned over the complex pipeline under the control panel. Just as he pieced together clues in a criminal case, he was now analyzing the path of the metal pipes. "Look, if this dam works like an engine, every engine must have a relief valve. When the pressure reaches this level, the machine must vomit the energy somewhere so it doesn't explode."

  "But the killer must have sealed that valve in the darkest part of the dungeon, the bottom floor," Macan said, looking at the ink-black mana leaking through the grates below. "Going down there is walking knowingly to one's death."

  "Aslan, Marry! You stay here," Eren said, his voice rising with the tone of a commander. "Stall the pressure by pulling the manual levers on the control panel as slowly as possible. Macan and I will go down and blow that valve."

  "But sir, if Lord Pitrosg is a traitor... why are we saving him?" Aslan asked. The young knight's hand was trembling inside his armor as he sheathed his sword.

  Eren stopped and looked into the young knight's eyes with a gaze that carried the fatigue of ten years. "We aren't saving the Lord, Aslan. We are saving this forest, the Elven Queen, and the possibility of justice manifesting in a courtroom rather than exploding dishonorably. If this dam explodes, the truth perishes with it. And I don’t want to just watch once again."

  When Eren and Macan descended to the Boiler Room at the very bottom floor of the dungeon, the temperature felt like the inside of a furnace. This was the most brutal point of the mechanism, where the underground river struck the massive turbine blades directly. From the grates under their feet, tar-black mana water, decomposed within the dam, flowed violently and with froth.

  "There it is!" Macan shouted, pointing ahead through the rising steam.

  A massive, rusty valve was practically sealed to the wall with dozens of mana chains. Right in the center of the valve sat the killer’s final "origami joke": a perfectly folded paper turtle. Representing patience and slowness, this figure waited with a mocking serenity as if to say,

  The narrative has been illicitly obtained; should you discover it on Amazon, report the violation.

  Eren checked the trigger of his steam-mace one last time; the needle of the pressure gauge was trembling right at the end of the red zone, as if it were about to burst. "Macan! While I break the valve's chains, you expand the mana leaks in the side walls with your axes! We need to divide the pressure of the main line, otherwise, the valve will blow us up the moment it opens!"

  Eren gripped his heavy metal mace with both hands and lifted it high. The mana tube inside the mace began to glow with a poisonous purple light, vacuuming the dense and filthy energy in the room. Eren gathered all the accumulated disgust and the rage he thought had subsided over ten years into a single strike.

  "This is for those children from ten years ago!" he cried.

  THUD!

  The shockwave emitted when the metal head of the mace struck the chains cleared the steam in the room for a moment and even threw Macan back a few steps. The chains shattered as if exploding, but the valve still wouldn't budge. From the massive walls of the dam, cracking sounds like the breaking of a giant’s bones began to come. The black mana water had now risen above the grates and begun to burn their boots.

  "Eren, the valve is locked! You can't turn it by hand; the metal is about to melt!"

  Eren tore a piece of cloth from his coat, wrapped it tightly around his palm, and placed his steam-mace into the valve’s handle like a lever. The veins in his neck bulged; his face turned crimson from the heat and pressure.

  "I... am a Chief Inspector..." he groaned through his teeth, his entire body trembling violently. "And this machine will stop in city... by rules!"

  The rusty metal of the valve screeched as it groaned under the immense pressure applied by Eren’s mace. For a moment, it was as if time had stopped; there was only the sound of blood thumping in his veins and that deep cracking noise in the walls of the dam. Then, suddenly, there was a breaking sound and the valve began to turn.

  "SHHHHHHH!"

  The moment the valve opened, the pitch-black, poisonous mana accumulated in the dungeon’s veins began to empty through the discharge pipes with a gargantuan force. The pressure was so high that the sound turned into a whistle that could burst eardrums. Macan tried to protect herself from this force by digging her axes into the side walls.

  "Get back, Eren!" Macan shouted through the rising black steam.

  When Eren separated his mace from the lever, he was thrown back by the jolt. When he fell to the ground, he felt the piece of cloth in his palm burn and stick to his skin, but he didn't feel the pain. He only focused on the slowing rhythm of the pistons above and the sound of the stopping gears. The engine was choking; the killer’s "ignition" was now out of fuel.

  From above, the joy-filled shouts of Marry and Aslan echoed. The uncontrollable rise of the dam had stopped; the dungeon had ceased to be a living monster and turned back into a cold pile of metal once more.

  Eren stood up with difficulty from the floor. He looked at his burned palm and smiled faintly. "Not today," he murmured toward the darkness. "Today, you will not sacrifice anyone."