Fleshpound

...a metallic tube slid in, right above the grip. Smoothly and silently.
  – "Where's the rest of our team?!"
  – "There's no time! Keep firing!"
  The lock slid into place with a silent click.
  – "There's too many of them!!"
  – "DISPLACE! DISPLACE!!"
  The piston, with lock, slid easily down into the tube, locking in place.
  – "FP!! FP!!! EVERYBODY, FALL BACK!!!"
  The spring, inserted into the piston and locked into place.
  – "KENT! GET OUT OF THERE!!! KENT!!"
  The top, slammed in and locked in place.
  – "Kent's down, WHERE THE HELL ARE YOU?!"
  The clip, inserted with a little click.
  – "IT'S ENRAGED!!! LEG IT!!"
  Reloaded, and aimed down the sights, and it hit me. We were screwed.
  – "McGrath, GET UP AND RUN! You're not killing it with that thing!"
  A character stood less than a hundred yards away, twice the size of a man, seemingly half-made of metal, trashing a car Kent used to stand on. All lit up in a crazy red hue, it was coming straight at me. A hell-of-a moment to get my gun jammed…