Regular rule-playing game progression

Except when the party is too stupid for morals and instead decided to end the world instead of compromising 5min with someone they assumed to be the BBEG just because she could talk to dragons and they had been attacked by a dragon once. Despite knowing that this woman was holding shut a literal portal to hell that Tiamat was ready to use. Ffs

I remember one session that went something like this, after I bowed out of it mid way due to being exceptionally busy with work, and also just... too much idiocy.

After the group had gone galavanting around, causing multiple mass casualty / ecoterrorism events by either completely missing or disregarding all the context clues dropped all over the place by the DM urging caution, suggesting things might be more complex than the party assumes they are...

... after a while, the grouo is encountering refugee wagon trains due to how they tackled major dungeon 2, got to big town 3 and it was more or less in a state of civil uprising due to a famine... all this shit caused by the group murder hoboing too hard...

The DM sets the group off on the next NPC driven adventure to stop a 'mad warlock', with a semi-plausible reason from the quest giver who has been stringing them along... but evil quest giver also asks them to retrieve a certain cache of magical texts from this warlock.

The group obliterates the warlock, mid summoning spell, summoning spell goes haywire, basically causes Oblivion hellmouth portals to start popping up, in an expanding radius.

The group tries to get the cache back to evil quest giver but oops, he's not where he said he would be, whole area is ravaged by demons.

... Then one of the group decides they have the requisite skills to be able to themselves read the cache of magical scrolls, written in an ancient, esoteric language, which must be read aloud to work properly... and that this is their only shot now at saving the world.

So this idiot more or less tries to read one of the Elder Scrolls... he chose, and rolled, poorly...

He causes himself to go blind, and insane, basically now experiences all of time simultaneously like Dr. Manhattan... now can only speak in the arcane tongue... which he does not know how to do properly, so now spacetime time is just warping and snapping and breaking around him wherever he is, so the rest of the party is soon turned inside out, blasted lightyears away or millenia back in time, and the world is obliterated.

... Bad murder hobos. BAD.

I have only watched evangelion once but I am sure that is a EVA painted over. I think during the ::: spoiler Tap for spoiler Eva flesh eating incident :::