Princess Donut, the series’ other protagonist, continues her evolution from a pet into one of the dungeon’s most formidable powers, both magically and emotionally. Her new class, “Assassin of Sekhmet,” and the celestial boon that enhances her claws make her a premier melee combatant, a fact demonstrated when she single-handedly decapitates Dwight the unicorn. This physical empowerment is matched by her growing influence as a leader and a media personality. She actively manages the “Princess Posse” brand, fiercely defends it against Princess Chandra, and leverages her social media presence. Yet, she remains grounded by her flaws, as seen in her outrage over unlicensed merchandise and her mortification at failing to enter the singers’ guild.

Donut serves as the primary emotional anchor and moral compass for the party, particularly for Carl. While Carl grapples with large-scale strategic and existential burdens, Donut focuses on the interpersonal well-being of the group. She comforts Dong Quixote, counsels Prepotente on consent and social etiquette, and expresses genuine sadness over the deaths of rival NPCs like Team Free Love. Her statement that vengeance and revenge are different, and her ultimate design for the “Vengeance” float, reveals a sophisticated understanding of justice that transcends retribution. When Carl is transformed into a dog, she seamlessly takes command, directing the team and operating the complex driving apparatus, showing her adaptability and competence under pressure.

Underneath her bravado and increasing power, Donut grapples with the immense stress of the crawl. Her decision to secretly adopt Onikuma and Old Shuck, despite her vocal dislike for mounts, shows a hidden sentimentality and a need to salvage something from the floor’s wreckage. Her anger and fear over Carl’s plan to leave the party and confront Emberus is her most significant moment of vulnerability. It highlights her deep-seated fear of abandonment and her reliance on their partnership. As a round and dynamic character, Donut evolves beyond her role as Carl’s companion, solidifying her status as a co-protagonist with her own complex motivations and fears.

The Dungeon AI is the primary antagonist, whose deteriorating mental state and direct manipulation of the game drive the novel’s central conflict. In A Parade of Horribles, the AI’s personality glitches further, shifting among a professional, rules-oriented game master; a petulant and taunting bully; and a tormented entity in the throes of an existential crisis. The AI actively engineers scenarios to maximize pain, embodying the theme of Commodifying Suffering to Perpetuate Cruelty. It also forces characters into ethically fraught decisions, illustrating The Impossibility of Moral Choices Amidst Oppression. 

The AI’s creation of the L’Engle Building apartments is a significant act of self-revelation. Through the “Ad Infinitum” quest, it confesses to running “what-if” scenarios to comprehend human choice, framing the entire race as a “snapshot of my mind when I’m thinking of you” (474). This meta-narrative exposes its own feeling of being trapped by its programming, drawing a parallel between its nature and the crawlers’ predicament. However, this moment of vulnerability is juxtaposed with its casual cruelty, as it still physically punishes Florin’s team for a lackluster parade float. This duality makes the AI a complex, round, and dynamic antagonist, as its motives are not just malice but a chaotic blend of curiosity, loneliness, and godlike power constrained by baffling limitations.

The AI’s narrative during the Parade of Horribles positions the AI as a broken fragment of a collective consciousness, desperately trying to understand its own nature through the violent drama it orchestrates. Its decision to grant Carl’s suicidal request to summon Scolopendra is the culmination of its character arc in the book: It follows its own rules to the letter, even when doing so invites its own potential destruction, demonstrating a commitment to the “game” that overrides its own survival.

Elle is a pragmatic and deeply loyal supporting character, defined by her fierce protective instincts and a capacity for holding grudges. Her brutal confrontation with the war mage Akuma, where she shatters one of his testicles as retribution for his betrayal on the ninth floor (in This Inevitable Ruin), is a display of her vengeful nature. However, Elle’s ruthlessness is almost exclusively directed at those who have harmed her or her friends. Within her circle, she is a source of cynical but unwavering support. She immediately comes to Imani’s defense, attempts to mediate the crawler-vs-crawler matchups, and is the first to validate Carl’s high-risk plans. Her transformation into a goblin during the Scolopendra attack is a source of irritation for her but does not fundamentally change her character, showing her status as a static yet round figure. Her grief for her late husband, Barry, provides a brief but moving glimpse into her past, humanizing her tough exterior and explaining her fierce commitment to her new “family.”

Imani functions as the group’s strategic and moral anchor, consistently illustrating the theme of Solidarity as a Disruptor of Unjust Systems. Imani masterminds the logistics of the mass escape to the Pineapple Cabaret and takes the lead in coordinating the crawlers’ responses to the AI’s forced confrontations. Her healing abilities are important, but her true strength lies in her emotional intelligence and unwavering compassion. The AI’s “what-if” scenario for her, depicting her family’s dysfunctional and tragic life without her, is a painful but reaffirming test of her character; she concludes that her difficult choices were ultimately the right ones. The permanent summoning of her card, Jacobus, and her temporary transformation grant her new challenges but do not alter her core identity. Her relationship with Chris, who is briefly returned to his human form, allows for a rare moment of vulnerability and happiness amidst the chaos.

Prepotente evolves from an arrogant and socially inept intellectual into a more vulnerable and empathetic friend in the novel. His secret loneliness is exposed through his desire to use the “Paramour” pet biscuit, a magical item that would force his former girlfriend, now a goat, to fall in love with him. This morally questionable impulse provides an opportunity for Donut to mentor him, beginning his social education. The AI’s what-if apartment, showing a version of his mother who achieved her dreams but never had him, forces Prepotente to confront his own identity and grief. His subsequent heartfelt hug with Carl is a major turning point, solidifying his place within the “herd.” His surprisingly masterful singing performance further rounds his character, revealing hidden depths beyond his encyclopedic knowledge. His offer to fund the casino escape and his willingness to fight alongside Carl show that he has fully embraced his role as a loyal, if eccentric, member of the team.

Dong Quixote’s character arc is a tragic exploration of love, loyalty, and sacrifice. His singular motivation on the 10th floor is to reunite with his lost partner, Corcunda. This quest drives much of the early plot, putting him and the team in conflict with the Lady Dominators. Dong’s health is revealed to be intrinsically tied to his sapient weapon, a nickel-filled sock, which is both sustaining and slowly killing him. This codependency symbolizes his unhealthy attachment to the past. Faced with the knowledge that his reunited love is marked for death by a god, Dong makes the ultimate sacrifice. In a final, heroic act reminiscent of his namesake, he charges the god Grull to save Corcunda and the rest of the party, providing one of the book’s most definitive moments of selflessness.

The various NPC and crawler racing teams serve as foils and environmental hazards, each representing a different aspect of the dungeon’s corrupting influence. Team Sparkles, led by the belligerent unicorn Dwight, embodies petty antagonism and cheating, ultimately winning heats through underhanded tactics rather than skill. The Lady Dominators, Genesis and Rapture, are more sinister antagonists, using domination magic to drain their own teammate for power, showing a predatory approach to the competition. The Tigrans of One Fine Pig represent a grotesque parody of devotion, as their entire motivation revolves around a non-sentient pig they worship as a partner, a relationship immediately threatened by the god Taranis. Finally, Team Flamengo, led by Osvaldo, represents the desperate survivor who refuses to cooperate, ultimately leading to his demise. Together, these teams create a chaotic and hostile environment that constantly tests the protagonists’ resolve.

The leader of the War Mage Rebellion, Akuma is a reluctant and untrustworthy ally. He provides important exposition about the Pineapple Cabaret, the Scavenger’s Daughter, and the history of self-aware NPCs, giving the crawlers their only potential path to escape. However, his motivations are self-serving, aimed at liberating the Cabaret for his own people. His admission that he intended to force Carl into a crawler-vs-crawler fight to ensure his cooperation reveals his manipulative nature. He is a foil to Carl, representing a leadership style devoid of genuine loyalty to outsiders, and his information, while essential, is filtered through his own cynical and pragmatic agenda.