2. The Plant Apocalypse
This one's pushing it a bit, I know, but there is a precedent. Sure, that precedent is none other than M. Night Shyamalan's The Happening, but it's still, you know, a thing. What separates this from the natural disaster apocalypse genre is its unnaturalness: solar spots may be unusual but it's not "plants release a neurotoxin that causes humans to commit suicide" unusual. It even sounds like it could have the potential to be cool, but it mostly boils down to Mark Wahlberg and Co. running away... from the wind. The Happening isn't the first film to feature apocalyptic greenery: Day of the Triffids and The Little Shop of Horrors both address the pressing issue of blood-thirsty foliage. These aren't your standard monsters in that King Kong never contained chlorophyll. As opposed to your usual monster apocalypse, in fact, the plant apocalypse is all about making the mundane a real threat. A NASA satellite survey a few years back suggests there are somewhere in the region of 400 billion trees in the world, more than 50 for every man, woman and child on the planet. If they ever decide to uproot and come after us, it could make a zombie apocalypse look like a walk in the park.