The party in this story are a group of low-level wizards (and only low-level wizards) who were tasked with completing their “last chance exams” at Wizard Academy™ for a chance to graduate with the rest of their cohort. It was a one-shot dungeon crawler style of game where we rotated the DM for every room. Given our level and abilities, rooms featured such challenges as battalions of house-cats, CR-reduced mimics and baby bugbears that still frequently required us to take long rests as the DMs swapped. After much trial and error (and only a few near deaths) we made it to the final test: a battle against a junk golem-style monstrosity that had access to wild magic.
Of particular importance: the current DM was an English/History teacher while Players One and Two both studied higher mathematics at university, and after an earlier incident the only serious rule we were following was “no retcons”.
*rolls particularly well* With a great tear, a portal opens to the Elemental Plane of Cats! Ten housecats immediately appear in the arena, and more housecats begin pouring through the rip in reality at an exponential rate -
Yes, that’s what I said.
That’s… that’s a lot of cats, dude.
Nah, it’s not that many.
No, she’s right, that’s a
of cats. *does the math* Yeah, see, if we started out with ten housecats, and assume that the exponential growth is per round per cat, you’ve got a hundred housecats at the end of next round, and over a thousand after that -
DM, starting to realise his mistake:
Look, all right, I misspoke, we’ll retcon that -
Hell no, you wouldn’t let me retcon licking the mimic earlier; exponential house-cats!
I don’t have enough minis for this…
Long story short, the house-cats killed the golem and almost killed us until someone Prestidigitation’d catnip back through the tear in reality.
“Exponential” is now a byword in our group for “poorly phrased description that will backfire horribly” and that DM has never used it to describe anything since.