The phrase “perfect storm” is used in this sense. A number of things coming together at just the right time to make a huge and devastating storm. I’ve heard the phrase applied to non-storm situations as well. It’s not an adjective, but we’re pretty loose in English about that.
seroutdipity?
Haplessness?
:golf clap:
This gets my vote!
Clusterfuck to me seems best, with perfect storm a close second. Perfect storm seems a little too bad-eventy, and I don’t like that it became a buzzword so soon after the movie. I didnt know “vicissitude” implied negative consequence; I’ll OED that as soon as I can.
Of course, clusterfuck is obscene. ::sigh::
But ‘out’ isn’t the opposite of ‘en’ so in a similar vein how about serenbumpity.
Cursed. Or curséd? Ill fated?
Trainwreck, snafu… not really what’s requested, maybe, but tryin’ to come up with ideas here.
But it’s turning into a real Katrina, huh?
Trainwreck’s good.
I’m probably addressing a zombie, but does this refer to Zembla, in Nabakov’s Pale Fire?
Fate, maybe? Especially in the Greek tragedy sense.
In D&D, rolling a 1 on a D20 is called a “critical failure”, often shorted to crit-fail. Then there’s the Internet meme of Epic Fail, though it doesn’t really include the idea of chance or randomness.
When in doubt, steal from the French.
merde