Player: I had an old 2E Halfling Hairfoot Fighter, Bow Spec... our group returned to our village, to find it had been recently sacked by Orcs! In our despair, we spread out and searched, I thought I detected movement in one of the barns and let fly an arrow. Killing his own mother.
DM: I tend to do this ALOT - I let the game's run too long, and in our bleary eyed exhaustion, start making mistakes. Most notably, Thanos (of Marvel fame) had found himself in the DnD universe - and had decided to do here, what he did there, Master Death, assemble an apparatus similar to the Infinity gauntlet - etc etc, well in the grand finale the PCs time/dimension travel to Titan before Thanos becomes a power, and kils him in a very short, unimaginative battle. Only thing - I can't, nor can any of my players, recall how we got from from the DnD world to ancient Titan... nor any story hooks as to why they would even attempt it.