He served under First Teron'tokal and Vorta overseer Yelgrun, who commanded a patrol sent to monitor the activities of the USS Lambda Paz, which was dispatched to the Tong Beak Nebula to verify intelligence that a Jem'Hadar breeding facility was being built on a planetoid in the nebula. Believing that he and his fellow troops were protecting unborn Jem'Hadar, Ulin'talag was uncertain that passive monitoring would assure the success of the mission to lure Starfleet into an ambush, considering the Starfleet ship would leave and come back with reinforcements. As a result, Ulin'talag dispatched the fighter he was commanding to shoot down the shuttles dispatched to take a closer look at the surface.
Out of a sense of obligation to face the consequences of his defiance of the First, and hence defying the Founders, he returned to the Dominion flagship afterward, where he was swiftly executed by Teron'tokal. (Star Trek: Lambda Paz: " Revenge a Dish Best Served Cold")