Yak'Talon was a Jem'Hadar soldier who served, in 2374, as the Seventh under the Vorta Keevan during the Dominion War.
After their ship crashed on a planet in a dark-matter nebula, located in Cardassian space, he was assigned to repair their communications system so they could send a distress call. This task would have taken ten days, and the Jem'Hadar had insufficient ketracel-white to last until then.
Yak'Talon and the rest of his unit were later killed in a deliberate ambush ordered by Keevan so that he himself could survive in Starfleet custody. (DS9: "Rocks and Shoals")