Yes, Commodus did fight in the Colosseum. History tells us that he participated in gladiatorial contests, which was quite unusual for a Roman emperor. In fact, he was known for his flamboyant displays and often fought against gladiators in staged bouts.
His actions were more about self-promotion than actual combat. Commodus wanted to present himself as a heroic figure, and by fighting in the arena, he sought to connect with the Roman populace. These spectacles were choreographed, and his opponents were typically less experienced, ensuring that Commodus emerged victorious. This behavior was viewed as both scandalous and absurd by some contemporaries, as emperors were expected to maintain a dignified distance from such bloody entertainments meant for the lower classes.
Commodus’ gladiatorial bouts, while entertaining to some, ultimately contributed to a decline in his popularity and were part of the reasons behind his eventual downfall.