“ 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?”
“ On a location with numerous webs, and at least one big spider, there is a something inside a cocoon. It is humanoid in shape, still moving. If the heroes free it (not before they kill or drive away the spiders), they meet a ... zombie!
The poor zombie wandered the dungeon alone, and tried to kill a big living creature (= a spider). The spider used the usual treatment, even if this victim did not look tasty. The zombie can be easily killed as any other zombie. It got but several doses of spider-poison, so can be something worth if it is extracted. You can mention to a druid or ranger the fact the spider had no poison anymore.”
“ A magician develops a new way to make scrolls and can sell more powerful spells for cheap. Problem is, whether the magician is aware of it or not, the spell's power comes from spirits trapped by the magic that makes the scroll. Once used to power the scroll, the spirit is driven mad by the forces that have ripped through it's being, and often develops a homicidal thirst to destroy the one who tormented it. The spell the spirit was used for may have left some residual power in the spirit to give it more abilities than it ever used to have.
Buyer beware!”