Queen Moonra reigns over the Indian Ocean, a realm of mermaids and mermen. Her empire faces a dire threat as climate change devastates marine life. Coral reefs bleach and vanish, fisheries decline, and dead zones emerge, leaving vast areas lifeless. Determined to save her people, Moonra embarks on a quest to uncover the cause of these catastrophes. As she travels, she witnesses widespread destruction and vows to fight back. Moonra's resolve ignites a war against humans, whom she holds responsible for the environmental collapse. She mobilizes her army, wielding advanced steampunk technology and biological innovations. They attack human supply chains, targeting beaches, ships, and aircraft. The conflict causes massive disruptions, cutting off human access to the oceans and severely impacting global trade.