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.
Woodrats - In a fantasy realm of cooshee (elven dogs/cats) it is to be expected that there is some sort of elven vermin. These mercurial rats are lightning quick, and are capable of hiding in plain sight. Other than this, they have no special ability.