Most of us have come to accept that dropping the kids off at the pool is going to be predictable, within reason. Maybe you're having a robust day and lay out a caber that a Scotsman would be proud of, maybe you're having a mousy day and peppering the bowl with niblets. That's your deal, and I'll not discuss it further. But texture and girth aside, we tend to expect it to not look like Slimer just shot out the back door and had pool party in the shitter.
The Black Whopper didn't just give you spinachy poops; it turned your ass-smudgings full-on Green Goddess green. The buns were supposed to be tinted with A1 steak sauce, and must have used some kind of amazingly concentrated form of the seasoning to provide the bad luck of the Irish that followed.
Pepto Bismol is another crap shoot for your crap, as the stomach medication has a habit of turning your ass into a portal to a dark underworld of seething black hatred. The bismuth in Pepto can combine with sulfur in your GI tract and turn as black as the souls of the damned. Just imagine the confidence you'll have in your diarrhea medicine if you take a few doses and then release a torrent of angry midnight into the toilet. That's your insides telling you it's time to try Imodium.
Slightly more terrifying that a Pepto obsidian squirt is the phantom white s**t you'll get if you have to endure a barium sulfate shake at the hospital. Barium sulfate is typically used when you have to have an x-ray or CT scan and the doctors want to see what's going on in your guts. The barium goes in, coats your insides, and helps scans pick up any areas of concern. They'll mix it into a shake or somesuch that you need to ingest an hour or two before the actual scan, and then you're good to go. Unfortunately for some, as the barium is excreted out the back door, it has a tendency to go all White Walker in your intestines and suck the soul out of your otherwise-healthy poop, leaving it a pale, terrifying husk of a white monstrosity that you'll probably stare at with an arched eyebrow for a moment or two before really hitting that flush handle hard.