satanophany
n. a visible manifestation of Satan

Potassium chlorate brings out the worst in gummy bears.

In their 1996 manual Chemical Curiosities, H.W. Roesky and K. Möckel introduce this demonstration with an invocation from the Talmud: “He who ponders long over four things were better never to have been born: that which is above, that which is below, that which came before, and that which comes hereafter.”

(Please don’t try this yourself.)