Female Changeling

The Female Changeling was a Founder of the Dominion and represented them in many of their dealing with the Alpha Quadrant powers during the 2370s.

She entered the Alpha Quadrant prior to the mining of the Bajoran Wormhole by Starfleet and was trapped away from her people. She was considered the leader of the Dominion forces within the Alpha Quadrant, though she left much of the organisation and prosecution of the war to the Vorta and senior Cardassian and then Breen military leaders. (Star Trek: Deep Space Nine)

The Muir changeling made direct contact with her to report on the Guyra IV Moonbase and the Starfleet and Klingon Defence Forces massing in the Guyra system. She cautioned Muir to be careful due to the limited number of Founders present in the Alpha Quadrant.

After the Dominion reinforcements failed to appear from the Gamma Quadrant and a vast number of Starfleet and Klingons ships heading to attack Deep Space 9 she ordered all her forces to retreat back into Cardassian territory. 

In mid-2374, Starfleet Intelligence believed their learnt of her location and travel plans and organised a Special Operations Command strike force to capture her. The intelligence proved to be false and was a trap with most of the SOC force destroyed, the Female Changeling was never in any risk.

After the Dominion was isolated and surrounded at Cardassia Prime she surrendered her forces and handed herself over to the Federation Alliance.