A necromancer marching with his army of death would likely be depicted with dark and eerie imagery, emphasizing the morbid and supernatural nature of the scene. The necromancer himself would likely be depicted as a menacing figure, dressed in black robes and carrying a staff or wand with arcane symbols carved into it. His face may be hidden or obscured, adding to the sense of mystery and dread surrounding his character.
Behind the necromancer, the army of death would likely be shown as a horde of undead beings, including skeletons, zombies, and other creatures that have risen from the grave. The sky above them might be dark and stormy, with flashes of lightning illuminating the eerie procession.