I’ve been toying with an idea lately to make the endgame in cataclysm more challenging. Some of the problems I have with progression in cataclysm is that:
-Lategame is too easy compared to early game
-If you can’t handle something, you just don’t go there. Avoiding danger is too effective.
-Danger only seems to come from monsters. Starvation or freezing to death hardly ever happen.
To solve this I give you “Events”! 
Basically, once you reach a later stage of the game (Determined by time spent in the world) occasional “Events” would start taking place. Examples of these could be:
-A nuclear/volcanic winter. For a few days everything is pitch dark and icy cold.
-A heat wave. For a few days, it’s extremely bright, hot, and food spoils a lot faster.
-Dimensional alignment. For a few days, random portals spawn through which eldritch beings come to harass the player.
I think these “Events”, and others like them (Please suggest your apocalyptic event in the comments), would solve all the problems named above, and make the game more !!FUN!!.
I rest my case.
Yeah I agree with this idea. There should be more random events and such. Kinda like Project Zomboid has that thing where if you survive long enough it gets harder to survive by making the zombies come to you and forcing you out of your home. Once you get more than 30+ jars of canned human meat “Hospital raid, Don’t ask” it gets quite boring. I say events like this would be cool to have implemented.
Destabilization of the connection between dimensions causes portals to open periodically. The portals can have many effects and differing intensities. Some examples:
[ul][li]Ice: Perpetual cold, think ice lab but not confined to lab environment.[/li]
[li]Hallucinogenic: Nether environment messes with players mind causing them to hallucinate uncontrollably while in the zone.[/li]
[li]Darkness: Severely reduced vision capacity in this zone, not aided by night vision.[/li]
[li]Madness: Hallucinations + severe morale penalty + disorienting (character occasionally steps in wrong direction). Could be a more intense type of hallucinogenic zone. Minimap and map blacked out or otherwise incorrect somehow?[/li]
[li]Freaky weather: Acid rain, weird electrical storms, etc.[/li]
[li]Nether colony: Nether flora and fauna have established a foothold.[/li]
[li]Contaminated: Almost devoid of life. No grass, trees, or wildlife. Water may be nastier than normal. Nether creatures and zombies may remain, but in smaller numbers than would be expected. Non-sealed food is probably contaminated somehow. Prolonged exposure without protective gear causes sickness? Maybe litter the ground with corpses of all sorts?[/li][/ul]
An earthquake causes an ancient underground nether temple to be revealed that could have a nether portal inside.
A group of bandits move in and claim a small town or section of town as their own and start expanding their influence and raiding other towns and settlements.
Serious real weather events. A New England blizzard is nothing to be trifled with.
I like your ideas! However, when I mentioned events, I meant something bound to a certain period of time, not a region as you seem to have interpreted it. When events are worldwide, but only persist for a few days, you can’t avoid the danger zone, resulting in a massive increase in !!FUN!!. If the events only occur in a certain region, they wouldn’t really add to the difficulty of the game.
EDIT: In case you did interpret it as I meant it, I apologize.
Well, the idea would be that the portals would appear periodically and would stay until you do something about it (what that is remains to be determined, but I have some ideas), and eventually there would be too many to avoid effectively. They could also grow and extend the regions that are affected making it hard to avoid as well.
I wouldn’t mind to see events or anomalies. One which covers time and affects the world globally and the other confined to specific regions, though much more chronically.
I’d like to add meteor showers/impacts to the list. Triffids came from somewhere, and perhaps other threats did too. We can get some H.G. Well martians walking around.
Or Alien Landings/UFOs. OC, that raises the oppurtunity for all kinds of mods.
Why not have both types? 
Configurable of course. I like both of these methods. I would encourage anyone who actually wants stuff like this implemented to make use of the bountysource system (offer cash for coders work). This is something I would definitely add a bounty too when I get some $.