thumb|right|Spawn's eyes glowing green with necroplasm[[wikipedia:Image:Spawn-baterang.thumbnail.png|thumb|right|Spawn bleeding necroplasm after being struck by Batman's Batarang|]] Necroplasm is a will-controlled magical substance featured in the fictional Spawn universe. It was originally indistinct/synonymous with psychoplasm, the substance of which Hell itself is composed. It is similar in properties, but special in that it can exist on Earth without needing to remain in one of Hell's spheres of influence as well as being allowed to traverse the mortal world without violating the non-aggression pact between Heaven and Hell. Necroplasm was a creation of the Grand-Mal Demon known as Leviathan and is exclusive to the 8th Sphere of Hell. He used it to create a demon in his own image, known