A young Romulan officer serving on the Bird-of-Prey that attacks the Neutral Zone outposts, whose breach of communications silence helps the Enterprise track the cloaked ship.
Decius is an officer aboard the Romulan vessel that crosses the Neutral Zone in the first-season Original Series episode Balance of Terror. He was played by Lawrence Montaigne, who later returned to the series as the Vulcan Stonn.
Eager for glory, Decius sends a coded report of the mission's success back to the homeworld, breaking the silence his commander ordered. The commander reduces him two steps in rank, and the old centurion warns that Decius has powerful friends who make him dangerous.
Throughout the duel with the Enterprise, Decius presses for attack where the weary commander counsels caution, and makes it clear he will report any sign of hesitation. He goads the commander into a final assault and dies with the rest of the crew when the commander destroys his own ship.