I've got a few generations of stories.
Starting with my father. Dungeons and Dragons, Second Edition. Dad and his friends were murder-hoboing through a dungeon made by my uncle, oldest brother of three. So far in the campaign, no structure the PCs entered was left standing. This included inns and taverns. So Uncle John decided new building materials were needed. And so began a glorious, insane scheme by Moroll the Somewhat Fetid, Sorcerlock Extraordinaire and Evil Genius.
Moroll had troll minions that could, as long as fire or acid were not involved, regenerate from ANY wound or damage eventually. This meant that, when he was running low on trolls, he would cut all his trolls in half and wait a week. Eventually, he found a way to profit on this: spread a troll army throughout the land and get paid to do it.
This led to the birth of Cubic Trolls.
You start with a box, maybe the size of a man's torso. Then you cut a troll into many pieces. Fill the box about halfway with pieces of troll, and wait a month. The troll grows into the shape of the box, because magic shut up. These are then advertised as the sturdiest, most indestructible building materials of all time, capable of stopping ballista bolts, and self-repairing! Needless to say, the scheme was a roaring success.
Okay, back to Dad & Pals in the dungeon.
The party walked into the grand chamber, probably full of loot, when spiders start crawling down one of the walls to attack them. My dad was a wizard, so he did what wizards do.
He launched an empowered, maximized Fireball at the wall.