Reports that the Dominion was developing a new class of extreme size and power have circulated for some time, but only with the loss of the USS Valiant was this rumour confirmed. The Valiant survivors revealed that the battleship was even larger than had been thought - twice the size of a Galaxy class starship and three times the strength. Had the ship been put into service it would have been a major threat to the Allies; although he was technically acting against orders, the Valiant's captain decided that he had to make an attempt to destroy the ship before it could enter service.

The Valiant located a potential weak spot on the battleship and managed to get close enough to attack it, but although the attack was successful the enemy ship survived and continued to return fire. The Valiant was destroyed during this action with most of her crew lost, but a few survivors managed to make it back to Federation space in escape pods.
The current status of the prototype battleship is unknown. It was apparently quite badly damaged by the Valiants attack, and is believed to have spent some time in shipyards after the battle being repaired. For the rest of the war there were no further reports of these vessels; it seems unlikely that the Dominion was unable to correct what was after all a fairly minor design flaw, yet they seem to have abandoned the Battleship completely after the Valiant battle.

But this was not the end of the basic design, however; a scaled up version of the Battleship design was used as the basis for the much larger Dreadnought type vessel seen - though not engaged - in the final stages of the war.