Another one for the way-back machine - also in the mid-80's.
I was home from the Bay Area, ready to play in a friends high entropy campaign. Another friend (down from Portland) brought his high level warrior (1/2 demon) and I was kitted out with my elven mage-thief. Between us we had way too many levels and enough fire power to level a small continent. The DM was loaded for bear, anticipating the devastation we'd caused the last time we were both home. And then the third player called and bailed on us...bummer. Scratch the quest we'd planned for months for. All was not lost though, as fortune shined on us and one of the low level game players happened to drop by.
We hired the poor low level thief as our point man, promising him he'd survive the experience (straight faced, no evil grins visible). Then we switched dungeons on the DM and went fishing... that poor thief died so many times that night it wasn't funny. At the time we didn't dock con points or many of the more sophisticated rules we've all implemented to stop just this kind of abuse. We cut him out of the gut of a giant lizard, scraped him up from under stone blocks, pulled him off the rusty spikes of several pits, etc.
We blew holes through that poor dungeon and left smoking ruin. It actually ended up almost campy as monsters started fleeing the dungeon. I think that poor thief died over a dozen times, and the DM gave him an extra level in trap detection as he's seen them all (mostly from the inside). We had plenty of healing stuff to keep him ticking.
We all had fun (even the DM) as he'd really wanted a cataclysmic event to shift events in his world. By mutual decision the high level characters retired as they were at the demi-ghod stage and the thief returned to his usual group with a heck of a tale.
Funny thing was, most didn't believe him as they didn't know Dave B. and I had both been in town that weekend. Then the DM announced the cataclysm and monsters running amok, and the great smoking pit where the wizards tower had been <G>. I actually got a phone call at home in San Jose to see if it was true, and if so why did I ruin the world? And why didn't we let the others watch!
For several years afterwards we threatened to reprise it just for the shock value <G>.