“ A massive iron key - 2' length, 20lbs forged from the bones and horns of demon-lords. When used with a massive portal - carefully built according to documents found in powerful books of evil knowledge, it will open into the realm of demons and allow them to flood into the world. The applications of this item for villains are obvious. Mortals touching this item directly will suffer very dire consequences.”
“ The heroes find the crumbling, overgrown ruins of what appears to be some sort of grand dining hall in the forest. Deciding that it is a good place to camp, the set up a fire in the center. However, they are woken in the night to see skeletons waltzing in the moonlight to organ music that emanates from the open air. The skeletons touch nobody, dancing around them all night.”
“ Feral teenagers:
Teenagers who run away from home to live in the wilderness may become feral. As they become more and more feral, they gain some supernatural powers (a la Peter Pan - ability to fly, things they imagine come true - possibly quite powerful), but at the expense of their humanity and ability to speak, comprehend complex subjects, etc. Maybe they have a leader: the most feral of them all.
A regression into a fantasy childlike state.”