Mood slime
Mood slime (also known as psychomagnotheric slime or psycho-reactive slime) is a peculiar form of ectoplasm with unusual empathic properties. That is to say, it reacts to human emotions, both positive and negative. Mood slime can have different properties depending on what emotions it's reacting to. Negatively-charged slime can create dimensional rifts that ghosts can use to cross over or empower them. Positively-charged slime can be used to weaken ghosts and effectively exorcise a ghost out of anyone they are possessing.
Fiction
Transformers/Ghostbusters
The Ghostbusters left a canister of mood slime inside Ectotron's vehicle mode. (Along with an occupied trap, empty traps, and enough crumbs to compose another meal). Ghosts of Cybertron Part 4 This mood slime soon proved useful when Ectotron was possessed by the ghost of Megatron. Though considering the small size of the canister and Ectotron's large metal body, the Ghostbusters decided the slime would work best inside of Ectotron. After Optimus was able to knock the possessed Ectotron onto his back, Ray clambered onto Ectotron's chassis and administered the mood slime orally. Shortly after, Megatron's ghost was expelled and Ectotron was left feeling disgusted. Ghosts of Cybertron Part 5
