Origin and Installation
Duplemar, like its sibling Valkines Gloandi and Forbrannir, was initially created on Fodra--presumably by Amarcians. It was then transported and installed on Ephinea in order to assist the man-made Lastalia with the transportation of water-type eleth.
 Uses and Consequences
Initially set up in a city, Duplemar is one of the two Valkines that had unforseen, adverse reactions to their surroundings. While probably intended to be located in what used to be Strahta's capital, the installation of Duplemar caused water eleth in the surrounding environment to become largely scarce, turning Strahta into the desert it is today.
Despite this, though, Duplemar is still capable of supplying Strahta with unlimited water eleth as intended--the majority of it showing up in Yu Liberte.