The Final Trial. Royal Guide to Monster Slaying, Book 4

Rowan embarks on an expedition to prove once and for all that she is the rightful royal monster hunter, in the fourth and final book in this fantastical series by New York Times-bestselling author, Kelley Armstrong. The time has come! After discovering the true reason for the monster migration, Rowan is on an expedition to ultimately prove that she is worthy of the ebony monster-slaying sword on her back.
She and her twin brother, Rhydd, their friends Dain and Alianor, as well as some other trusted advisors - and the ever-growing group of monstrous companions - are on a mission to help protect the dragon living in their homeland and are travelling to kingdoms beyond to make their case. But not everyone agrees that people can live peacefully alongside monsters, especially when new terrifying creatures appear.
It will take everything Rowan has to fight off threats of all kinds, from both monsters and people. It won't be easy, but if she succeeds, she will become Royal Monster Hunter at long last. An illustrated guide to the creatures appears at the back of the book.