Dekton is a half-Spartan, the son of Arete’s brother Idotychides, and half-Messenian. He serves the Spartan army as a helot and mightily resents the Spartans. He is an atheist, the only one Xeo has ever met. He marries Harmonia and has two children, one of them a son, Messenieus. He repeatedly proves himself to be a brave warrior and is even offered Spartan citizenship, but refuses, gaining a reputation for treasonous sentiments. Nearly executed for treason on the eve of Thermopylae, he’s turned loose on the Greek frontier instead, thanks to Alexandros’s intervention on his behalf. Arete also reveals that Messenieus is not his son, but Dienekes’s. Later, Dekton reveals valuable information to the Spartans, enabling them to infiltrate the Persian camp and prepare for a Persian sneak attack. He is granted his liberty by Leonidas and, in gratitude, becomes a Spartan warrior himself, later sparing Gobartes’ life.