Young Trill candidate for joining whom Jadzia Dax evaluated, and who earned her recommendation by piloting a runabout through the wormhole.
Arjin is a young Trill initiate who comes to Deep Space Nine in Playing God to be evaluated by Jadzia Dax as a potential host for a symbiont. Expecting a harsh mentor like Curzon, he is surprised by Jadzia's relaxed manner, and she finds him guarded and pursuing joining mainly to please his father.
While they work together, a runabout brings back a tiny expanding proto-universe that may contain life. Dax encourages Arjin to aim higher, and he flies the runabout carrying the proto-universe back through the wormhole, navigating safely and winning her positive recommendation.