Marius Titus is the main character in Ryse: Son of Rome.
Marius's journey begins when he comes home to his family. After a training sword fight with his father, Leontius, his father, says, "It's the first time when son beats father. "After that, they hear Marius' mother scream, see that was being chased by barbarians. After the fight with the barbarians, Marius and his father come to the fountain and see Marius' sister and mother massacred, and Marius's father swears that he will kill every last barbarian. After a fight to find Platius, a close ally of Leontius and could be in danger, this proved to be correct as they were too late and could only watch as Platius was killed be archers. After another fight against barbarians, Marius' father is stabbed by Emperor Nero's sword, which was held by a barbarian. Marius would later discover that these barbarians were, in fact, Emperor Nero's minions. After that Commander Vitallion puts Marius in the Fourteenth Legion. Soon after, Marius and fellow soldiers head to Britannia and once they arrive, quickly become under barbarian attack. Marius leads the counter-attack, rallying the surviving Roman troops and nearly single-handedly preventing the destruction of the remainder of the fleet, which impresses Vitallion. Marius is promoted to Centurion.
After receiving reports of a rebellion at York, Marius heads north to aid the defeated legion stationed there. Upon capturing King Oswald and his daughter Boudica. Basillius, the son of the Emperor Nero, reveals that his brother Commodus has been captured by the barbarians, whose whereabouts are unknown. Basillius, threatens Boudica and forces King Oswald into revealing the location of Commodus, who has been traded to the fearsome men north of Hadrian's Wall. Basillius orders Vitallion and Marius to retrieve him. After crossing the border into Caledonia, the party is ambushed, Vitallion is taken hostage by barbarians and Marius is separated from his legion. Marius makes his way into the enemy camp, freeing and rallying captured Roman soldiers along the way. He kills the barbarian leader Glott and rescues Commodus and Vitallion from being burned inside a giant Wicker man.
Once Commodus and the legion return to York, where Commodus has Oswald killed in front of his daughter lighting up a rebellion in the ranks of the Brittons. That's when the Emperors kids flee the scene leaving Marius, Vitaillion and the rest of their men to fight off the Britons. After putting up a fight they realize that there is no hope and flee to the ships. Once there Vitallion offers to sacrifice his life to save his men but Marius decided to do it himself claiming that Vitallion needed to appeal to the council about the crimes of Commodus and his brother. And so Marius stays behind fending off the hoards until he's overpowered and thrown in the sea.
However Marius was not dead, the goddess Summer comes into play saving his life and turning him into a vengeful warrior like Damocles and so Marius makes his way back to Rome where he finds hungry people tortured by the Praetorian Guards. That leads him to take up arms against them becoming a criminal. So he forges a Damocles mask along with a black armor and goes to a gentlemen's club where Basillius hosts fights, then he won the fights earining an invitation to the Colosseum tournament hosted by Commodus. After receiving the papers he kills the emperors younger son in a basement room and left.
Once in the Colosseum Marius overcomes all odds earning him a fight with Commodus. During the fight Commodus spared to attempt to cheat but fell short to Marius and was a victim to his sword. After killing him he moved on to threaten the Emperor himself before running away. But he was intercepted by Vitallion outside who was glad to see him again and took him back to the legion. From there he helps to defend Rome from the barbarians lead by Boudica. He then is enlisted by Nero to defend him. He blindsides Nero by telling him that he is Damocles and is about to kill him. Nero reminds him that he cannot be killed by Marius's sword, only by Nero's own weapon. Nero summons guards to defend him and he escapes. Marius is distracted by the god Aquilo as Nero back stabs him with his dagger. Though he is weak, Marius proceeds to kill multiple Praetorians he then tackles Nero off of a balcony. Nero land on the pointed end of his statue's sword and dies. Marius, having enacted his revenge finally dies.
- Marius Titus shared his name with the two separate historical figures: Roman Republic's general and seven-time consul Gaius Marius and Roman emperor Titus Flavius. Marius was the nomen (clan name) of the men from gens Maria, the clan which the historical Gaius Marius belonged to. Titus was a praenomen (forename), which were also used by Titus' father and brother, the emperors Vespasian and Domitian.