Jiren is assumed to have a sense of justice similar to the rest of the pride troopers, however he is shown to be very stoic and serious about the tournament, due to being aware of the stakes. He is a very brave and disciplined individual. He is an extremely strong warrior, and he's very obviously proud of it. 

(In terms of accent, it may be North American, or English.)
(No idea for this voice, just make sure it's deep and intimidating, other than that. Do what you feel is right.)