We have mostly used it as the core for some open ended one-shots where the results bled into other games, either assaulting a coven stronghold in a dungeon of my creation or coming round deep in the B2 Caves of Chaos.
As such, we did very little to pin down a shared canon of how the million spheres worked, but had a lot of shared authorship pretty explicit upfront. There was a real sense of no true gazetteer, and though it never came to it, if someone was to profess a truth that was game-bendingly convenient, I’d ask they Test their Luck to determine if it were truthful or wilful misbelief.
Some of the most absurd parts came out of combat (in our last game, the Vengeful Child broke his sentimental sword in the very first round of combat) and my favourite parts are the mien tables — I’d advise writing some for every set of NPCs