As soon as King Andrias possesses the Calamity Box, he founded Leviathan Defense as private armed forces, controlling Amphibia. Whole continent is under the oppression.

Leviathan Defense has taken over most of the natural habitats in Amphibia, converted them into military bases, to enslave the captives and anyone against the King.

Knowing their key resource for developing new armament, Sasha is on a mission to liberate a mining facility and stop their plan.