Marcan V

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Marcan V was a class M planet in the Marcan system within the Klingon Empire. It was a hot and arid world, with temperatures and gravity slightly higher than that of Qo'noS. It was also a resource-rich world, one of the first conquered by the Klingons in their early days of expansionism, and a strategic one. Marcan V apparently has no indigenous sentient life forms. (GKN short story: "A Song Well Sung")

During the Battle of Marcan of the Dominion War, the last two surviving vessels -- the IKS Pagh and a Jem'Hadar ship -- both crash-landed on Marcan V. The last surviving Klingon, Klag, son of M'Raq, single-handedly killed the seven Jem'Hadar and one Vorta who had also made it to the surface. This feat earned Klag the name "Hero of Marcan V". (TNG novel: Diplomatic Implausibility)