Tomoshibijima No Pandora Shiyaku

The Cannibal Shark Void. That was the beginning of it all. Ten years later, science and technology research and marine experiments are flourishing in the "Dragon Palace," a mobile marine research city built on the sea. However, there is a terrible "legacy" hidden there. Some fear its existence, some seek its existence, and some try to find a ray of hope in its existence.
Is this hidden "legacy" hope for mankind or despair?

(Source: Kadokawa, translated)