It's always hard to review a book that is part of a larger franchise, like this one for the Dragon Age game series. How much I actually enjoyed this for its writing is hard to pin down as the important context that The Calling gives to Dragon Age lore is unmistakable. So, I'll start off with saying that any fan of the games will thank themselves for reading this - once more we enter the dark past before The Blight, the story slowly inching towards building the scene we all know and love from Dragon Age Origins. Gaider as a writer is clearly passionate about his creations, characters that only appeared for a handful of quests years ago being given pride of place in his books instead of being shoved aside for the larger names. It's something I personally appreciate about his work. 
 The book itself is unfortunately set in The Deep Roads for the most part, an unmapped labyrinth of ancient underground pathways and caverns originally built by the Dwarves. In the present day they are mostly overrun by Darkspawn, and it makes for a somber experience for the reader. By the end I was feeling just as desperate to leave as the characters were. I would have appreciated some more chapters giving context to what was happening on the overworld - page upon page describing fear, darkness, and frustration did get a little repetitive by three quarters through. The pacing slowed a little too much even though the ending revelations were worth the trek. 
 Would I have enjoyed this if I wasn't a fan of Dragon Age? No. I think this is too entrenched in existing lore to be a good recommendation for those looking for a new fantasy book without knowing anything about Dragon Age first - it's my appreciation for the series that makes me much more forgiving to the issues I would have had otherwise with the plot. The author depends on the reader being familiar with the locations mentioned. 
 The book before this, The Stolen Throne, isn't necessarily a must read beforehand but it will give much more context to the mentions of Katriel and the friendship between Loghain and Meric.