Barry arrives. The cube activates. Silence.

Barry vibrates his hand at a subsonic frequency. Not to attack—to feel . The air currents. The pressure changes. The tiniest tremors in the floor caused by Echo’s movements.

“So how do we stop someone we can’t hear, see on radar, or touch without losing our minds?”

“On my Earth, Echo was a failed audiophile. She lost her hearing in a lab accident. She doesn’t want noise. She wants the absence of error . Lossless. Perfect. Unforgiving.”

He phases into a blur.

A high-security Kord Industries data vault. Not a single decibel of sound escapes its lead-lined, vacuum-sealed walls. Inside, Dr. Vanessa Cradle, a meta-criminal known as Echo , places a small, obsidian cube onto a pedestal. It absorbs all ambient sound—her footsteps, her breathing, even the hum of the lights—into utter, perfect silence.