Where would manga be without gory violence? Where indeed, huh? This is a real short entry, just to drop in one little hint: Blood (at least in manga) is a viscous, shiny liquid. When it trickles out of a cut, it will move slowly, clump together in a single trail, and have a shiny specular highlight. Check out this page from Jos Fouts's chapter of Unseen Hand where Megaera the Fury lays the smack down, as the kids say. That's pretty much it.