Before the destruction of Taris, he announced the matches between the amnesiac Revan and Deadeye Duncan, Gerlon Two-Fingers, Ice, Marl, and Twitch.
The announcer did the commentary on the first fight that Revan was in as the "Mysterious Stranger", which was against the worst duelist, Deadeye Duncan. Revan defeated Deadeye and the announcer told Revan that he needed to do more to impress everyone.
Since competing in the Taris Dueling Ring is optional in-game, some duelists may not be fought, if any. In this case, the announcer is never heard. If the character is dark-sided and player chooses to complete the dueling ring side quest, the announcer would announce Revan's illegal death match with Bendak Starkiller.