What is the author's style in The Underdogs a Novel of the Mexican Revolution by Mariano Azuela?

The Underdogs is told in a third-person limited perspective. The "limited" here is quite limited; not only is the reader confined to (with very few exceptions) Demetrio's army and its immediate concerns, but rarely is the reader privy to the thoughts and feelings of characters. Dialogue is instead given the large responsibility to relay thoughts and feelings; as a result, dialogue is many times obvious and "on-the-nose," meaning characters speak exactly what they think and feel. On the other hand, dialogue can also serve as the author's "soap box," an opportunity to present thematic material and musings on the nature of the revolution that would otherwise be difficult to insert naturally into the unfolding of events. This kind of dialogue is relegated to Luis and to a lesser degree Solis and Valderrama.

The choice of this limited perspective is appropriate to the very nature of Demetrio and his men, who are characterized largely by their inherent lack of introspection or an appreciation of a larger picture. Cursed with a myopic worldview, Demetrio has no appreciation of the larger meaning of the revolution, no sense of politics, and no concern for the long-term results of his actions. He lives hand-to-mouth, town to town, battle to battle, a soldier following orders blindly. His men are even more extreme in this regard, content with looting and pillaging. The limited perspective and choice to not include thoughts and feelings is thus a kind of symptom of the myopia that plagues the protagonists.