In 2372 after the start of the Dominion war, the Federation and the Klingon Empire salvaged several Jem'Hadar attack ships. From the study of these ships, the two powers agreed that they required a vessel capable of fighting these formidable ships on equal terms. So was born the Avenger

Built at a Klingon shipyard, Federation and Klingon engineers created a vessel of formidable power.

It's firepower outmatched a vessel twice it's size, mainly due to the two phased polaron cannons, which make up the vessels main armament. The ship also has two phaser canons mounted in two turrets and three quantum torpedo launcher (Two forward and one rear).

The most unique feature of the vessel however is it's propulsion system. The ship is propelled using ion propulsion, which makes it faster than most vessels.

The vessel was designated as a ship killer, designed to arrive at a target, attack and flee at high speed. However, the vessel was only used once during the war, attacking a Jem'Hadar battle cruiser and it's support . The attack was so severe that after only five minutes of constant fire, the cruiser was all but destroyed and the support vessels in disarray.

After that attack, the two powers agreed that the vessel was a unique weapon and that it's existence had to be kept a closely guarded secret.

Fearing that the vessel would be "commandeered" by the Klingon Empire after the war, a group of Section 31 officers "stole" the Avenger from it's base and hide it deep within Federation space, where it has lain undisturbed for over a decade.

Until Benjamin Hiem's heard about the ship.