Erikson explores the tension between fate and free will by personifying fate in the god Oponn. Oponn's actions and qualities and the characters’ reactions to them underscore the arbitrary and uncontrollable nature of fate as well as individuals’ power to assert their free will despite what luck throws at them.

Oponn, god of chance, is the personification of the “prod and pull” of fate (32). The two sides of fate—good luck and bad luck—are represented by the Oponn twins, the lord and the lady. Erikson’s choice to personify fate as a pair of twins rather than a single being asserts that fate is fickle and two-faced. This concept of fate as two-faced is reinforced by the Oponn’s symbol, a coin. The symbol of the coin establishes another of fate’s qualities: randomness. The author chooses to represent Oponn’s influence as a flipping coin, something that is quintessentially random and arbitrary. Fate’s randomness is further reinforced by how the god chooses to exert influence over the world: Instead of taking direct action through possession or sending in faithful servants like the Hounds, Oponn opts to toss magically imbued items like the coin and sword into the world and then see what happens.