Dimidium is another planet in this the same universe as Aequilavium, created for the meme of having a name in Latin that means the same thing as Aequilavium.
Dimidium is half ruled by magic and half ruled by science. Those born in each hemisphere can never cross between, as the fundamental forces on the other side of the planet will reject their biology. Those born on the Dimidium strip can venture all over the planet.
All metals are liquids in the magic half of Dimidium and the ocean in that hemisphere is made of liquid metal.
All species in the magic hemisphere have metal blood. There is a slave trade that herds valuable metal blooded species to the science hemisphere where their blood turns solid and they are mined for their resources.