Shinkai Densetsu MEREMANOID

In the underwater world of Mer, the once peaceful kingdom of Bars launches a devastating war against the principality of Moslem and the kingdom of Agadia. The sudden rise in Bars' military strength remains unexplained, as it quickly challenges larger and more powerful regions. At the same time, two young spiritual knights, Jo and Oz, earn a living by eliminating marine monsters. However, the local population is wary of them, fearing their abilities and perceiving them as a danger. Against their will, Jo and Oz become involved in the conflict against the army of Bars, which is now led by forces of darkness.