The Swallowing Dephs Dimension

It would be the dimension you would get to by the ancient city portal, it's an extremelly dark dimension with an oneiric/nightmarish vibe, it's a vast dimension with biomes stretching like in LB world. so the other way around of the nether, you would want to get the other ancient city portals in order to move faster in this dimension, this dimension is one vast, bottomless ocean (the swimming animation and visual effects would continue if you went below 0) around 30% of this dimension is covered in glaciers that tower cliffs to 200 blocks up that ocean. This dimension is filled to the brim with uncanny, cambriam looking creatures, much like the overworld this dimension has an day/night cycle, with the sky having many dim celestial bodies. This specific dimension would also obey no minecraft textbook rules, mobs can break and place blocks at will. generated chunks will automatically be deleted after a while and the presets of the generated terrain would change with time (why it's called swallowing dephs)