Trolls have existed on this planet for as long as humans. This is what I was told and what I translated to Tub. The first mention of them in recorded history is from ninth-century Norway, when the nefarious creatures began showing up in song, verse, and bedtime stories to keep misbehaving children in line. According to Norse folklore, trolls are one of the Dark Beings, the purest embodiments of evil, and they scurried from between the toes of Ymir, the mythic six-headed Frost Giant whose murdered body became the universe in which we live; his bones became the mountains, his teeth boulders, and so forth.
Guillermo del Toro, Trollhunters
horror, middle-grade-fantasy, trolls