YMMV / Firebird's Son

• Base-Breaking Character: According to the reviews, Harry in the first book by reacting like an actual kid would to the unfolding events. The author even snarks that the readers expect Harry to act like a mature man in his twenties rather than an pre-pubescent child.
• Harsher in Hindsight: Do the details of goblin reproduction squick you out? Well Goblin Slayer infamously shines a massive spotlight on that idea and made it well known to those in its area of the internet, and it came out several years after this fic.
• Rooting for the Empire: Reading the first fic will lead you to advocate Harry join Voldemort and way waste to the fic's magical world. Sure you'd probably still want Harry to put Voldemort down for all he has done, but only after he and Harry team up and set the Sabbat on fire. The later fics had this reduced as Voldemort's crimes, on top of the horrible things he and his allies do to Harry in the first book, make it clear he's no better.
• Too Bleak, Stopped Caring: It can be hard to read the fic and like even 25% of the named characters, with many of the main characters being among the 75% you want to die (Harry thankfully stays pretty firmly in the likeable category). The world is a pretty miserable place and the idea of it ever getting better is a bit hard to believe.

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