Once night falls, however (isn't it remarkable how all the spooky stuff happens at night?), this horse undergoes a frightful [ transformation] [[Chronology - Volume #|✣ ]]. It snorts! It growls! It has sharp teeth! It grows horns! It's impervious to normal weapons! It [ breathes fire] [[Chronology - Volume #|✣ ]]! Which is to say, it generally turns into just the kind of nightmare that you really don't want running around your camp. All told, not a bad outcome for a battle with a real live nightmare. It might be that Othar Tryggvassen bought this horse and named it "Spooky."