The Behuam is the ocean and area the surrounds the main continent, except for around the Sea of a Thousand Souls. It is completely impassable. The Behuam is death incarnate. While the Sea of a Thousand Souls is deadly, with a skilled captain, crew, and sheer luck, you can make it through. However, there is no surviving the Behuam. If you travel even a millimeter inside of it, you're dead. No matter how well you might feel, sailing or swimming around in the area for a bit, the moment you leave, and you will leave, you die. Sometimes. the corpses don't float out. Sometimes, when you go in, you never come out. Diaries report days of endless torture at the hands of unknown monsters, the pages filled with thoughts directly from the minds of the unfortunate victims.
Scientists and wizards have tried, for many millennia, to pierce the secrets of the Behuam, even being the subject of much discussion for the Giants, the one secret they could not conquer. The Behuam has been here for a long time, far longer than even the gods remember. It is a natural law of the universe for the Behuam to kill anyone, and to forever be here. It is as natural as the way the gods made the universe, yet unnatural to a frightening degree. No one knows how it came to be, and no one wants to know.