Radon Trinitrite Astatide (BC torture)
A REALLY rare compound of radon, nitrogen, and astatine. It is only found at 0.000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000e000000000000000000e0e0e00e0e0000000000000000000000000000000000000000000000000000000001% of all the matter on Earth, so it can't really be proven to exist. The first cases of encounter of this dangerous compound was in 1034BC, by someone called Pnixus-faissel Hammoundburg. It won't surprise you to say that he died instantly. There was no further encounters ever since. Hence the nickname: BC torture.

All fiction. If there is actually something like this occuring or occured, it is absolute coincidence.
Teacher: Gimme an example of a substancial compound or I'll hang, draw and quarter you.
Boy: BC torture, or Radon Trinitrite Astatide (BC torture).
Teacher: What the heck?
Boy: Go look up urbandictionary.