Commodus battled both professional gladiators and wild creatures. "In his gladiatorial combats, he overcame his opponents with ease, and he did little more than injure them, since they all surrendered to him, but only because they knew he was the emperor, not because he was actually a gladiator," Herodian wrote. Commodus also killed several animals in the arena, including a lion, a bear, and a tiger. He died during the third game of a four-game series against Marcus Aurelius Antoninus. The cause of death has been debated by historians; some believe he was murdered while others think he died of natural causes. The emperor's body was taken to Rome where it was put on public display for three days before being cremated. His ashes were then scattered in the Tiber River. Commodus' wife and daughter were also killed during the reign of Marcus Aurelius Antoninus. His son, Britannicus, who was only nine years old at the time of his father's death, became emperor under the name of Lucius Aelius Caesar. However, he was also murdered after only six months on the throne. The last genuine gladiator, Perennius, was released from prison shortly before the outbreak of the Civil War. He participated in the battle of Actium where he was cut down by Antony's cavalry.