The CDS Thagangreon was a Cardassian Kulinor-class starship of the Cardassian Union's Central Command in the 24th century. The Thagangreon was in active service around the year 2377. (TNG video game: Armada II)

No history or fate is established for this vessel as its designation was randomly selected for a ship by the game software.
Kulinor-class starships
CardassianUnion BororthargCathongrunCorarandFodradForkithGladrargGlareonGlereonImgidronKarargathMaringrukMeldrargMorarmornOradrargOrmukRodrimRothongrornSangrakThimarThuradrargTorandThagangreonThareonThasharthim CardassianUnion