Red Sea
A nebulous terrain spanning half of the Milky Way, the Red Sea is a supermassive cloud of bright gases slowly floating its way towards the Centre of the Yonderverse. Its origins date back to the Big Bang. During the Big Bang, the Red Sea was flung approximately 170 billion trillion megaparsecs away from the Centre of the Yonderverse, and ever since it has been crawling its way back.
A Mysterious Purpose
Nobody knows why the Red Sea exists. It seemingly serves no purpose to the Yonderverse as a whole, unlike every single other thing that exists, has existed, or will exist. Take Astral Seas as an example; they provide a concealing habitat for several space-faring animals, such as lordricarrs and mistbreathers.
Many religious believers believe the Red Sea to be the evaporated blood of Aavar, as some religions believe this God of Gods to be deceased. The leading religious theory is that the Yonderverse existed in some other form before the Big Bang, and the heat from the Big Bang overpowered and killed off Aavar, subsequently evaporating his body and blood.
A Slow Stroll to the Centre of the Yonderverse
The Red Sea travels at approximately 5 miles per hour, barely faster than the average walking speed of a human. The flakes of rubrunite present in the Red Sea is attracted to whatever is present in the Centre of the Yonderverse.
The Centre is much too dangerous for anyone to explore so whatever lies there remains unknown, and thus, a mystery as to what attracts the Red Sea. Many believe it to be something magical.
I love that it's trundling off at 5mph.
Haha, thank you! <3