The amazon.com product description:
Evil had cast its shadow over the kingdom of Rethwellan. When Idra, leader of the Sunhawks mercenaries, failed to return from a journey to her home, Tarma and Kethry, warrior and mage, set out in search of their vanished leader.Oathbreakers is the sequel to The Oathbound, and where I liked that one, I loved this book. It's got one of my favorite scenes between the main characters. Unfortunately, it's also absolutely full of spoilers so I don't want to give it here (and it's about three pages long). Suffice it to say that it's where the book title comes from.
Despite the slightly grimmer tone to Oathbreakers, there are still plenty of moments to make you laugh - usually involving Leslac. As well, we get a look at some of Tarma's other talents as a child-minder and teacher.
Like some of Mercedes Lackey's other early books, Oathbreakers has a section of songs allegedly by and about Tarma and Kethry and pertaining to various events in The Oathbound and Oathbreakers, some of which are absolutely hillarious. I definitely enjoyed reading through them at the end of the story.
Read for the Valdemar Reading Challenge and the Hardcore Re-Reading Challenge.