Instead of Díaz directly telling the story to the reader, he creates an aesthetic distance by speaking through the novel's narrator Yunior. Yunior provides analysis and commentary for the events he is relaying in the novel. His speech often exemplifies code switching, switching rapidly from a lively, Caribbean-inflected vernacular, replete with frequent usage of profanity to wordy, eloquent, and academic prose. This runs in parallel to several central themes of the novel regarding identity, as Yunior's code switching alludes to a struggle between his Dominican identity and his identity as a writer. Code switching between Spanish and English is also central to the narrative itself of the book, as characters switch back and forth as they see fit.
The narration of the book also shifts away from Yunior to another character at several key moments in the story. In chapter two, Lola narrates her own story from the first person. This is foreshadowing of the intimacy between Lola and Yunior yet to come. The beginning of chapter two also features the use of second person narration, rarely used in literature.
Diaz's use of Yunior as the main narrator of the book strengthens the idea of the novel as metafiction. Yunior reminds the reader consistently that he is telling the story, as opposed to the story happening in its own right.
The "Brief Wondrous Life of Oscar Wao" makes extensive use of footnotes to the point that many of the characters are developed in the footnotes in addition to the story. Rather than just provide factual background, Yunior's narrative continues in the footnotes just as it does in the body of the novel. When describing Oscar’s deep love of science fiction and fantasy literature, Yunior continues in the footnotes: “Where this outsized love of genre jumped off from no one quite seems to know. It might have been a consequence being Antillean (who more sci-fi than us?)... ” The presence of Yunior's footnotes, therefore, remind the reader that there is always more to one's story.
Yunior even makes reference in the footnotes to his present life earlier in the novel than when he describes it in Chapter Eight. “In my first draft, Samaná was actually Jarabacoa, but then my girl Leonie, resident expert in all things Domo, pointed out that there are no beaches in Jarabacoa. ” Yunior thus builds the writing of the novel and his relationship with Oscar into the greater history of the Dominican Republic. The many science fiction references throughout the novel and footnotes emphasize (Yunior believes) the fantastical elements of Dominican history. Yunior cites the fall of Mordor and the dispelling of evil from Middle Earth from The Lord of the Rings trilogy as a complement to the fall of Trujillo.
The footnotes contain many references specifically to the reign of Rafael Trujillo from 1930 to 1961, providing historical background on figures like the Mirabal Sisters, who were assassinated by Trujillo, and Anacaona, an indigenous woman who fought against the invading Spanish colonialists. While referencing historical figures, Yunior frequently includes the novel’s fictional characters in the historical events.
“But what was even more ironic was that Abelard had a reputation for being able to keep his head down during the worst of the regime’s madness-- for unseeing, as it were. In 1937, for example, while the Friends of the Dominican Republic were perejiling Haitians and Haitian-Dominicans and Haitian-looking Dominicans to death, while genocide was, in fact, in the making, Abelard kept his head, eyes, and nose safely tucked into his books (let his wife take care of hiding his servants, didn’t ask her nothing about it) and when survivors staggered into his surgery with unspeakable machete wounds, he fixed them up as best he could without making any comments as to the ghastliness of their wounds."
Yunior thus builds a context for the Dominican history, where the characters are used just as much in the footnotes as they are in the body of the novel.
Many of the footnotes ultimately connect back to themes of coming to a new world (underscored through the novel’s references to fantasy and sci-fi) or having one’s own world completely changed. Trujillo’s reign as revealed in the footnotes of the novel becomes just as dystopian as one of Oscar’s favorite science fiction novels.
Díaz moves between several styles in the novel as the narrative shifts to each of the characters. Oscar's speech reflects an autodidactic language based on his knowledge of fantasy, 'nerd' literature and his speech is filled with phrases like “I think she’s orchidaceous” and "I do not move so precipitously", whereas Yunior "affects a bilingual b-boy flow" and intersperses it with literary language. The story of the De Léon family is told and collected by the fictional narrator Yunior and the New York Times critic Michiko Kakutani has described the voice of the book as "a streetwise brand of Spanglish." He often gives his own commentary and analysis on the events he is relating in the story and sometimes reveals failings in his own life, both as a narrator and a person: "Players: never never never fuck with a bitch named Awilda. Because when she awildas out on your ass you’ll know pain for real."
His informal and frequent use of neologisms can be seen in sentences such as a description of Trujillo as "the Dictatingest Dictator who ever Dictated" or his description of the effectiveness of Trujillo's secret police force: “you could say a bad thing about El Jefe at eight-forty in the morning and before the clock struck ten you’d be in the Cuarenta having a cattleprod shoved up your ass.”
"The Brief Wondrous Life..." also oscillates back and forth between English and Spanish. Yunior peppers the English-speaking novel with Spanish vocabulary and phrases and certain English sentences are built with Spanish syntax: "Beli might have been a puta major in the cosmology of her neighbors but a cuero she was not."
Oscar lives his life surrounded by the culture of fantasy and as Oscar describes them,"the more speculative genres", and the language of these cultures is strewn throughout the book along with Spanish. Brief phrases relating to games like Dungeons & Dragons and tabletop role-playing game terms are used as common colloquialisms: "He [Oscar] could have refused, could have made a saving throw against Torture, but instead he went with the flow."
The novel first hints the style of magical realism by stating that the notion of fukú and zafá were popular in locations like Macondo, a fictional town used as the main setting in the Gabriel Garcia Marquez’s novel One Hundred Years of Solitude. As Solitude is renowned for its elegant use of magical realism, the narrator of Oscar Wao expresses that this novel will also be heavily intertwined with the concept of fukú and zafa as the novel’s contents are filled with fukú and zafá. Surely enough, many magical, supernatural events occur in the novel such as the godlike mongoose’s rescuing Belicia and Oscar, and those events are narrated with mundane tone as if they were natural.
Magical realism of the novel serves a crucial purpose by enabling the juxtaposition of the supernatural, intangible being and a mortal. With magical realism and the following quotation from the narrator, “It was believed, even in educated circles, that anyone who plotted against Trujillo would incur a fukú most powerful, down to the seventh generation and beyond”, the novel equates the two main antagonists of the story, fukú and Trujillo, by describing Trujillo as supernaturally powerful as fukú. Thanks to this juxtaposition, when Trujillo becomes assassinated, the novel successfully conveys that even the most powerful supernatural being can be defeated, ultimately implying the theme “Nothing is impossible”.
Other readers, however, reject the inclusion of this novel in the "Magic Realism" genre, which includes explicitly supernatural works by Murakami, Calvino, Kundera and Marquez, on the grounds that the "magic" in "The Brief Wondrous Life of Oscar Wao" is family folklore, and not a necessary plot element.