Nature is always coming up with clever ways to rid the Earth of humans. In this one, Ian and Liv talk about a lethal cloud of carbon dioxide that is released from a lake in Africa, which smothers and kills almost everyone within miles. Lake Nyos is the culprit, but even more shocking, this isn't the only time this has happened.

Also, Ian didn't cut a burp during the editing process. Liv gets her "Stranger Things" fix.