“ An alchemist enchanted his equipment to produce even more powerful alchemical compounds, potions and the like. Unfortunately, it is not well-known that he had different sets of equipment for different processes: If the wrong set of gear is used, the result will invariably fail to function. It's not a cursed item, just something that's hard to figure out.”
“ While it is within your purview to write long-spanning histories of your world, it is largely unnecessary. If you are running an RPG, do this instead: make a bullet point list of important events that affect the world today, and mysteries that people still don't know. Let these fuel your adventures.”
“ The Pcs discover an ancient, dusty oil lamp, somewhere in the bowels of a dungeon. Naturally they 'rub it', and out pops a wizened, old djinn. So far so good. Then it speaks...
'Ah at last, at last I am free! Now grant me my wish!'
When the PCs explain that they are the ones that should be granted a wish, the malignant djinn explains to them that his particular oil-lamp has a curse placed upon it. Whomsoever releases the entity inside shall be geased to grant the djinn's wish to the best of their ability.
Groans ensue from the party. The djinn rubs his wrinkled hands, grins, and proceeds to name his wish. What could it be?”