Comic books, science-fiction, and fantasy literature all play an important role in Oscar's upbringing and identity, and each is incorporated into the novel to reflect the world he lives in. Diaz has said that to dismiss the novel's reflexivity with fiction and fantasy is to do to the novel "exactly what Oscar suffered from, which is that...Oscar’s interests, his views of the world, were dismissed as illegitimate, as unimportant, as make-believe", and that the novel asks the reader "to take not only Oscar seriously but his interests seriously."
The novel opens with the epigraph: “Of what import are brief, nameless lives…to Galactus?” Diaz has said that this question can be read as being directed at the reader, "because in some ways, depending on how you answer that question, it really decides whether you're Galactus or not." In the Fantastic Four comic book however, Galactus is asking the question of Uatu the Watcher, whose role is played out in Diaz's novel by the narrator Yunior, indicating to Diaz that the question is both a "question to the reader but also a question to writers in general."
Early in the novel, Diaz aligns Oscar with comic book superheroes: "You want to know what being an X-man feels like? Just be a smart bookish boy of color in a contemporary U.S. ghetto...Like having bat wings or a pair of tentacles growing out of your chest." Diaz hints at possible latent abilities or qualities Oscar may possess that will reveal themselves or develop later in the novel.
The novel describes the history of relationships between dictators and journalists in terms of comic book rivalries as well: “Since before the infamous Caesar-Ovid war they’ve [dictators and writers] had beef. Like the Fantastic Four and Galactus, like the X-Men and the Brotherhood of Evil Mutants, like the Teen Titans and Deathstroke”
There is also a strong suggestion that the fantastical element of Oscar’s life is a powerful method for him to relate to other people and to the world around him. When he examines his own body in the mirror he feels "straight out of a Daniel Clowes book. Or like the fat blackish kid in Beto Hernández's Palomar." Oscar's vast memory of comic books and Fantasy/Science-fiction is recalled whenever he is involved in the text, and his identity is multiform, composed of scraps of comic book marginalia.
Diaz creates a distinct link between human beings' performative nature and the masks required to express it, and the masks worn by superheroes. When Oscar meets Ana, one of the many women with whom he falls in love, he notices different aspects of her life and "there was something in the seamlessness with which she switched between these aspects that convinced him that both were masks". Diaz connects the removal of masks with both the intimacy that springs from vulnerability and the concept of identity, hidden or otherwise. Oscar's infinite capacity for empathy and connection with other human beings is a superpower in its own right. Contemporary masculinity and contemporary power structures leave no room for vulnerability, but for Diaz, "the only way to encounter a human is by being vulnerable." The "man with no face" who reoccurs in several parts of the novel can also be read as a sort of mask embodying the fukú.
Fantasy and science-fiction
Diaz frequently uses references to works of science-fiction and fantasy. These references serve both to illuminate the world that Oscar lives in and create a parallel between the supernatural events in fantasy literature and the history of the Dominican Republic. In the opening pages of the novel, the narrator quotes Oscar as having said “What more sci-fi than Santo Domingo? What more fantasy than the Antilles?” One of Diaz's frequent references to J. R. R. Tolkien comes when he describes Trujillo: "Homeboy dominated Santo Domingo like it was his very own private Mordor." In another section, Felix Wenceslao Bernardino, an agent of Trujillo is metaphorically described as the Witchking of Angmar.
Near the end of the book Diáz comprehensively links the fantasy world of Middle-Earth with the world of the Dominican Republic and the novel.
At the end of The Return of the King, Sauron’s evil was taken by “a great wind” and neatly “blown away,” with no lasting consequences to our heroes; but Trujillo was too powerful, too toxic a radiation to be dispelled so easily. Even after death his evil lingered. Within hours of El Jefe dancing bien pegao with those twenty-seven bullets, his minions ran amok−fulfilling, as it were, his last will and vengeance. A great darkness descended on the Island and for the third time since the rise of Fidel people were being rounded up by Trujillo’s son, Ramfis, and a good plenty were sacrificed in the most depraved fashion imaginable, the orgy of terror funeral goods for the father from the son. Even a woman as potent as La Inca, who with the elvish ring of her will had forged within Banί her own personal Lothlόrien, knew that she could not protect the girl against a direct assault from the Eye.
Twice in the novel the mantra "Fear is the mindkiller" is repeated. The phrase originated in the Frank Herbert novel Dune and Oscar uses it to try and quell his own fear near the end of the story, to no avail.
Also, Diaz references Stephen King on a number of occasions, including a reference to Captain Trips, the fictional virus that wipes out mankind in The Stand, and a mention of being "flung into the macroverse" by "the ritual of Chud", a nod to the ending of It.