I think the 'other apocalypses we know of' is meant in a generic 'These are other types of Apocalypse in different cultures that come to mind now'. Of course, there are many more, like undead, plague of illness, animals going rampant, and more.
Most of these topics just feel like streams of consciousness with fanatics trying to frame the discussion so that it becomes a coherent thread.
Undead? You mean the Zombie mode of Civ VI? What has it to do with dynamic weather???
Maybe some pockets of humans turned cannibal after being isolated for thousands of years, the native American tales of the reddish giants that ate their victims sounds pretty nasty,
but I guess those weren't Undead by any mean...
The pestilecence turned thousands into living deads, but there was a cure, just not enough for everybody...
The 7 sacred oils bears the keys for ancient medicine remedies, the Oil sacred to Kronos, was known to cure Cancer in Indian and Chinese medicine.
It all came out from Africa, developed in India, China, and maybe also the Americas.
The Voodoo lore of the Pirates of the Caribbean is similar, ill sailors that didn't have access to the medicines...
No, really, I meant stuff like the inversion of the Axys, losing the magnetic shield... possible exposure to space radiation could have caused Animals to mutate
and potentially become very aggressive... untill the system would not stabilize again...
These are the other kind of Apocalypsis I had in mind.
Change in the gravitational effect, also could have cause gigantism, and even entire continents to float over water...
some metal rich rock could even have floated in the Air...
If we have to go "altered reality" I'd rather choose some Avatar like kind of scenario, or the Earth turned like Mars is today...
depending on which kind of Apokalipse... or planets alignment...
Today Mars could be hospitable and Earth a dry desert much like Mars or even a Venus like environment...