The North Sea of the Central Continent was a historical site known for its unstable weather and high-level beasts.
There were icy regions, to the point that vast blocks of ice formed in the sky, creating unimaginable rains that could sink large ships. At the same time, in areas not so far away, one could come across hot places where the sea boiled!
The entire climate in that region was utterly abnormal, with the presence of storms that could change ships' routes by thousands of kilometers in a matter of minutes!
And although there are hardly any islands in that region, most of the few that did exist were flying islands, which constantly changed location and altitude.
In addition to these unstable climatic and geographic factors of the North Sea, there was still the presence of powerful sea beasts in that region. After all, there was a region of high spiritual concentration, ideal for great potential spiritual beasts to develop.