- Alas, Poor Scrappy: Halsey had always been something of a Canon Sue in the Halo franchise before this book, and, although she wasn't outright hated, many fans wanted to see her get called out. However, no one wanted to see her suffer through the sheer hatred she has to endure in this book, and the vast majority of fans miss the old Halsey.
- Base-Breaking Character: Reactions to the depiction and characterization of Catherine Halsey, already a controversial figure among the fandom for her methods in the SPARTAN-II program, and Admiral Margaret Pargonsky, already a controversial figure for being the head of ONI, have split the fandom even more.
- Broken Base: Fans are divided over the Halsey hate: It's either been a long time coming, or the writer should shut up and focus on the story.
- Designated Hero: The leadership and agents of ONI, because after a war that killed billions of your own people, violently undermining the most prominent pro-peace Sangheili leader is just the way to go.
- Designated Villain: To the author, Dr. Halsey is the embodiment of evil, and she won't let you forget it.
- Fanon Discontinuity: Many Halo fans like to pretend this book doesn't exist, if they don't flip out in anger at its mention. Most notably, the fan-wiki Halopedia documents all the canon from Glasslands... but isn't above passive-aggressively reinterpreting it in their favor. Just look at this excerpt from the Catherine Halsey article.Halopedia: Many of those unfamiliar with the internal dynamics of ONI and the SPARTAN-II Programnote have come to interpret Halsey and her work in a highly negative light. [...] Such views often have their basis on information provided by the Office of Naval Intelligence,note which has frequently used highly selective or outright false informationnote to shift the blame for some of ONI's more questionable decisions on Halsey alone.
- Fridge Logic: How does Lucy, who is, like every Spartan, able to smash an Elite's face inside-out with her bare hands, not cause any real damage to Halsey despite slugging her at full force?
- Rooting for the Empire: Given how much ONI seems to want to start a new war right after the old one, you might find yourself rooting for the author's chosen antagonists.
- Strawman Has a Point: Chief Mendez makes an (apparently self-loathing) attempt to blame Halsey for the monstrous crimes which he himself helped commit during his tenure in the SPARTAN-II program, even claiming that the SPARTAN-III program was morally superior because it used volunteers instead of kidnapping children. Though Traviss's own sympathies seem to be with Mendez, readers tend to agree far more with Halsey, as she points out that six-year-olds can't truly volunteer and that all of Mendez's claims to be better than her are self-serving lies.
- Unintentionally Sympathetic: Doctor Halsey becomes this after suffering a brutal hatchet job courtesy of the author, which comes on top of her finding out that both John and Miranda have died in short order (as far as she's aware).
- Unintentionally Unsympathetic: Chief Mendez comes off as a far worse monster than Doctor Halsey due to his attempt to deflect his own role in the Spartan programs.
- Likewise, Kilo-Five's arming of terrorists to fight against a noble alien like the Arbiter makes them appear as Designated Hero types at best and Villain Protagonist ones at worst. With a long-term case of Stupid Evil due to the fact that said terrorists are rather open with their desire to continue their war with humanity.
- The Woobie: Halsey. She's trapped in a Dyson Sphere with people who have suddenly come to despise her all of the sudden and take turns yelling at her for various things, the most notable of them being the Spartan Program, which she had to do for the sake of humanity and has been wracked with guilt over her entire life. Even her decades-long friend, who was just as involved with it as she was, turns on her and tells her that he hates her for making him do it, and that she's a horrible person. She ends up yelling at an Engineer out of stress, and one of the Spartans punches her in the face for it. Then, they finally find a way to contact the UNSC, and she's immediately told that several months passed on the outside compared to the weeks within, during which her daughter died. Nobody feels sorry for her, and then she's placed under arrest by one of her students and someone she considered a surrogate daughter, and is given a "The Reason You Suck" Speech before being carted away. The end.
YMMV / Halo: Glasslands