What are the last two secrets of the dwarf in "The Truth is a Cave in the Black Mountains"? How does he leave Calum?

The other two secrets involve the dwarf's ability to run all day without trouble and the other is remarkable strength for a small man. He doesn't kill Calum, but leaves him on a ledge with a useless arm and a broken leg. The dwarf climbs up easily, and promises to return but not before a year has passed to equal the time his daughter spent tangled in the thorns.