The smallest ocean and the warmest, The Kourā Expanse is the southern ocean of Abmarah and includes the shattered Blood Sea, teeming with life, islands, and civilization. The most prominent feature in its eastern half are the Mauoro Islands including the island of Xeycahiti, known for its tropical climate and numerous active volcanoes controlled by the Excansuyu Alliance. The control of the ocean belongs primarily to the underwater civilization of Tritons known as the Aethian Dominion. They live in vast underwater cities, built from coral and quartz.

A subset of the ocean is the Blood Sea, which used to be the southern half of Aurial before the Cometfall. Containing thousands of shattered islands, it is a shallow sea full of ruins and many vying factions, such as the Crimson Empire, the Lunar Collective, the Pirate Lords, as well as the Cinoh Shogunate, a japanese and indonesian inspired island nation. The Blood Sea further contains the Cometfall Sea within it, a yet-unclaimed sea that was the epicenter of the Cometfall, said to be cursed. Much of the Blood Sea flows deeper down into the Noxila Ocean of the Underdark, which is said to be the secret fifth ocean of Abmarah. Various trenches and caves connect the two oceans through the shallow oceanic crust, and many of these entrances are guarded by Tritons.