Pguqium

Once a shining jewel of knowledge in the Multiverse, Pguqium is currently a plane of scattered and sparsely populated islands, the remnants of the world after being flooded by the plane's god of the unknown in the Drowning of Pguqium.

Poquilos, the Sunken City
Once a great city, using bridges an magic to sprawl across several towering islands, Poquilos now rests silently at the ocean’s floor, its non-gilled inhabitants and normal scrolls destroyed by the years underwater. But even before the Drowning, the plane was dominated by water, so much so that nearly everything of value had some manner of magical waterproofing, leaving the city, and much of its writings pristine, almost as if it had been built there from the start.

The Island
While several islands still break the surface of Pguium, an old myth of a utopic island has become a desperate hope to the few surviving Sailors on the Sea. The Island is said to be a large tropical paradise, big enough to support the ungilled survivors, rather than just one of the countless wet rocks that pass for islands now. How many sailors actually believe they will find the island rather than just holding onto to that one last fragment of hope is hard to tell, but those that don’t believe it might be out there somewhere usually find themselves in the Sea one way or another.

The Trench
Shirking many names over the years, the deepest part of the ocean is once more known simply as the Trench. Every Pguqiun that has attempted to chart its lightless depths has ended up dead, either by the Trench or shortly after giving up, cursed by their ambition. With Pguqium now ruled by fish, it is only visited by those that prefer the darkness.