YMMV / The Labyrinth of Spirits

• Ass Pull:
  • The entire array of new details and info about characters from The Angel's Game can feel like this, as the only perspective about them we previously had were in that book, which by this point of the story has been retconned as just a bunch of in-universe delusions. The fact that the new versions of those characters are quite unsympathetic, especially compared to their old incarnations, doesn't exactly help.
  • The existence of Alicia and her role in Fermín's past come out of nowhere in relation to The Prisoner of Heaven - they are essentially a revision of a background that was also a revision of his original background.
• Base-Breaking Character: Alicia. A refreshing and cool addition to the old cast, or an unoriginal, amoral vamp that gets tiring very quickly?
• Captain Obvious Reveal: That Leandro is secretly evil, and likely going to betray Alicia either directly or indirectly, is almost impossible not to see from his first appearance. His politeness, his role as Alicia's seedy handler and the fact that this is her last mission before retirement are all so cliché that it might have been shocking that he was not a villain.
• Contested Sequel: While readers were unanimous that it was a Surprisingly Improved Sequel towards The Prisoner of Heaven, how the book compares to the other two is divisive. There's the agreement that the book is an impressive work, which for some makes it great, but some see its story as unnecessarily complicated and hard to follow with its large cast, not to mention its unceasing retconning of old characters and backgrounds, which includes denting a pair of relationships of established characters.
• The Scrappy: Daniel. Many readers disliked his portrayal as an ineffectual amateur detective and aspiring writer in The Shadow of the Wind, and his portrayal in The Prisoner of Heaven only doubled down on his worst traits while making him even more of a non-entity in his own story. Now, as if this was little, he's a weird, creepy, possessive almost rapist who's even less proactive in saving his own family. In fact, he plays virtually zero role in the endgame, sitting back and letting Fermín and Alicia save the lives of him and his entire family while he chews his wife out and mopes around the bookstore he runs poorly. Zafón seems to be openly welcoming readers to hate him at this point after trying to make him the hero of two previous novels.
• They Changed It, Now It Sucks!: The new, "true" characterizations of David Martín and Isabella Sempere. She is the biggest offender, as she gets turned from a troubled, morally difficult yet ultimately nice young woman into an eccentric sex maniac with a terribly disfunctional background (and whose recollections of sex encounters sound like she is a literal rapist) that nonchalantly makes the devoted Mr. Sempere a cuckold. Adding this to the revelation that David Martín actually reciprocated a rather creepy love that was originally an one-sided teen crush, some people complained that their whole re-characterization sounds like straight out of really bad fanfiction.
• Too Bleak, Stopped Caring: It can be difficult to keep invested due to how gratuitously dark and aggressive the story gets, not to mention how the plot takes twists to make the worst of every situation from the previous continuities. There are a ton of villains, characters who feel like villains, and characters who turn out to be villains, and even the established heroes of the tetralogy take a level or two in jerkass, making it so that the reader barely has a single character to relate to. Arguably, the two most sympathetic characters are a chivalrous pervert who spends most of his time getting drunk and talking about women he wants to have sex with in between saving his friends' lives, and an emotionally disturbed, alcoholic agent of Franco's secret police who harbors upsetting sexual fantasies about the people she's investigating and who kills people in increasingly brutal ways en route to expose a fascist conspiracy.

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