>>53296674That one's a bit of an egregious example, that exact Kobra managed to re-grow its body (yes, I know how bullshit that sounds, but that's how the manga itself explained it).
Better example would be Gio killing the two magmar after Red wouldn't, but we weren't shown the killing blow there (which reflects the difference, gratuitous violence is A-OK, when itgetsbetter, but actual death is kept strictly off-screen).