These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
Complete Monster: Leland Gaunt is a very different kind of a monster villain, a genial and well spoken owner of a little novelty shop that just happens to have your heart's greatest desire in stock. He's willing to sell it to you for a paltry sum and a little favor. This is a harmless prank to play on your neighbor. What you don't know is that your "needful thing" is in fact a malevolent charm that will make you paranoidly obsessed over it and drive you into murderous insanity, not to mention that all the harmless little pranks are designed to thrive on old grudges and insecurities, exploit all the dirty secrets your neighbors (and you) have and stir up all the incipient feuds, turning people against each other until your whole town tears itself apart with weapons that Mr. Gaunt helpfully supplies. Even if you're spared by the slaughter and general madness, it is only so you could realise that you're partially responsible for it and kill yourself. Mr. Gaunt will just stand there at the window of his little shop, savouring chaos and death, like he'd done countless times before all across the world. He'll also collect the souls of everyone who dies in the fallout, even though he admits he doesn't need any more souls. Just to add insult to injury, said "needful things" are actually pieces of junk that are magically disguised to look like treasures.