A Mer Gateway exists...
One formed by the Voice of the Mermaids. Its origin begins with Poseidon who lights the celestial sounds of the Cosmic Door to swirl and open like a pool of watery stars blessed also by Triton.
It is a chorus of Mermaids joined by Faeries at the point of meeting where many Angels gather too spreading the Cosmic Song as they add their own light harmony.
Realms join together to spread light as it streams pictures of their Worlds to us.