That’s no moon ...
Two young nobles, enmity between their families. Where have we seen this before?
When a local farmer discovers something at the bottom of his new well, the fate of the land will hang in the balance.
This mountain chain was once vast and impenetrable, but had the misfortune to named in the binding spell of a mighty demonic(godly?) being, namely that when the Great Mountains are forgotten, then shall it be free.
Believable magic, like ordinary physicis, operates according to some invariable laws that always result in some kind of cost or "bounce back". The grater the magic, the more it should cost the character physically, emotionally, and spiritually.