Marine Phenomena 

Two weeks later...

Minos was sailing alone through the vast Ancestral Sea, at this instant, more than 75% of his course to where the signal from the previous map was taking him.

Minos had been traveling with haste to the central parts of that sea for the past few weeks since sending the great shark into the Spatial Kingdom, having ignored several floating and even land-based islands in his path.

There were no large islands in the Ancestral Sea. The nearest island of relevant size to that sea was Stone Island and the Marine Empire, which lay in the South Sea.

But small islands, the size of human cities with up to 5,000 inhabitants, existed in this sea, some located in the most central area of this gigantic territory.

In particular, the land islands closest to the center of the Ancestral Sea had a volcanic presence as a typical distinguishing feature, from which people could even see them hundreds of miles away.