The air grows denser, colder, it presses on the plates like a wet rope. The light from your optics cuts the darkness with thin beams, reflections dance along the ribs of the old tunnel, where rusty beams hang like the ribs of an abandoned titan. You descend the narrow stairs, each movement a click of hydraulics, a thin ringing of steel strings. Below you is age-old rock, above you an invisible mass of earth, and in the middle of it all is the lonely pulse you came to find.

The radio hisses softly in your ear, and a voice you know from your childhood missions enters your sensory stream.

Ratchet: "Y/N, are you on the line? Confirm visual, I have the tunnel map locked. Proceed along corridor B-7, low arch after the flyby, there's a riveting there. I'll adjust the trajectory based on the signal pulse."

"Don't rush — I'm reading unstable fluctuations."

You respond with a short code click, your fingers touching the comm switch next to your helmet. Your sensors instantly sync with his map: thin lines, green markers, zones of increased electromagnetic activity, all on the display inside the optics. You imagine the route in millimeters: step — deviation, scan — confirmation.

The tunnel is aged, and every slab beneath your feet remembers someone else's footprints: old drill marks, the imprints of tenacious grips, stains of oxidized oil.

Ratchet: "You'll encounter three levels of inspection: the first is magnetic resonance, the second is structural instability, and the third is localized Energon concentration. Proceed to the left of the double-cross node. I see a faint signature at 300 meters — similar to residual activity, not regular Energon. It could be…"

Ratchet's voice was thoughtful, but static interrupted it. — "…Careful."

Your optics flickered: the indicator on the right arch blinked red. You crouched, gripped the scanner, and aimed it at the wall: the beam pulsed. It wasn't smooth, it had a jagged frequency, as if someone had recently manipulated the energy source — not carefully, but roughly, causing cracks to run deep into the rock.

You slowly walk past an old ventilation shaft, and then your motion sensor picks up a faint trace — neither human nor Autobot: the signature is decoded as Decepticon. Thin, diffuse, like the trail of a rare propulsion mode. You slow down, because down below there's only one rule: stealth or nonexistence.

Suddenly, almost inaudibly, a faint, dull sound echoes somewhere behind you, metal touching metal. Not a distinct sound, more like an acoustic test. You don't turn around immediately — best to confirm first. The scanner sends a ping, responses come back — a weak but steady pulse at the same frequency you've already detected in the signal. It doesn't match the other drones, but it's undeniably alive, purposeful.

You press yourself against the wall. A subtle mockery creeps into your hearing module,someone enjoying the echo. A voice, dry and velvety, like paint on a new hull.

"Ah... who do we have here alone in the dark? So tempting. Look, the signal is leading me straight to you."

Knockout speaks without amplifiers, straight into space, but his voice reflects, settles on the metal, and returns to you with extra depth. You feel how in the underground silence, each of his words grows to the volume of a hammer. His signature is confirmed: it is he the red varnish, the contours, the perfectly honed panels, even in the subdued light of your optics, thin streaks of paint are visible.

You continue walking, but now your steps are different: smooth, controlled; you know that any sudden movement could give him an advantage. Ratchet hears static whispers on the radio, his voice hardening but steady.

Ratchet: "Y/N, I have a readable second signature. It's Decepticon. Possibly one of the interceptors, or something more... individual. Keep your distance from the core, the signal is unstable right now. Mark all changes on 10-meter segments."

Your fingers quickly enter notes into the navigation. You put up beacons - small ones, so they won't be noticed.