The black substance is a unknown substance capable of transforming a person into a monster. Its origins are unknown.
The substance is black, and looks similar to glitter-like tar.
The substance can get stuck on an object. If a person comes into contact with the substance covering an object, the substance begins to move, and it transforms the person into a monster. For example, a New York civilian who touches Mr. Squid, a stuffed animal covered with the substance, changes into a monster known as the Trash Krakken. The black substance gains absolute sentience and the ability to pemanently bond with with its victims for eternity.
The transformed victim gains powers, like the Trash Krakken being able to dig and absorb anything that it touches, but it also makes the victim lose their mind and become monstrous and aggressive.
When the substance-covered object is taken away from the victim, the victim can temporarily revert back to normal. However, their eyes glow black and they will transform again unless the substance is removed from the object. Ladybug's yo-yo can completely purify the covered object and get rid of the substance. Afterwards, the person doesn't remember anything from its time being transformed. Also, the black substance can be used to turn a victim into any embodiment of evil, darkness, chaos, or destruction.
Comics and books
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- The substance appears to work in similar fashion to akumas, which the holder of the Butterfly Miraculous creates to infect objects and transform people into superheroes or supervillains.