During the Dominion War, Starfleet began a number of plans to bolster their frontline with newer ships such as the Defiant, Sabre and Akira class, all built for combat.
However they also began to bring older Starships out of mothballs and either refitting them, or in some instances, constructing entirely new vessels in their shipyards. These are some of those vessels, the "Frankenstein Fleet" as well as the Centaur class and Yeager.

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