Panel 4: I believe that "KSHANGG" is a sound FX that I borrowed from my late friend Toren Smith, who I believe coined it to accompany the strides of Shirow's "Landmate" mecha in the translated manga Appleseed—though I suppose it's entirely possible that this might be yet another one inspired by Frank Miller, as both of us were fond of cribbing from his unsurpassed oeuvre of clever and percussive FX choices.

Panel 4: Uh oh!  This might not be good!  SPOILER: This is, in fact, not good at all.

-Adam Warren