Cardassian cruiser class related to the Galor, built in secret by the Obsidian Order for its doomed strike on the Founders.
The Keldon-class was a Cardassian cruiser closely related to the Galor-class, with additional hull sections and heavier armament.
In Defiant, Thomas Riker's raid into Cardassian space with the stolen USS Defiant uncovered a secret Obsidian Order fleet of Keldon-class ships being built in the Orias system, without the knowledge of the Cardassian military. That fleet, fitted with cloaking devices, joined a Romulan Tal Shiar squadron in The Die Is Cast for a strike on the Founders' homeworld, and it was annihilated by the Jem'Hadar in a trap laid by the Changelings.