The Iron Rider concludes A Dance of Dragons as it is the final companion novella to the main series. While these stories don't add too much to the main series, if you liked Princess Leena, you will want to pick this up. It's not too long, and can easily be read in a single sitting. It's decent, although the main events in this story go a bit too smooth I think.
Thanks to the publisher for providing me with a free copy of this book in exchange for an honest review!