Merfolk

The Unknown Ones are an unknown species seen within Ulduar glass-work and in ancient Tydenborne mythos. The Kul Tiran Tenochtri descendants of the Tydenborne believe they were friends of the Tydenborne before the Curse of Flesh. As they've been silent, most Tenochtri believe they were murdered by N'Zoth or are currently under his enslavement. Some Tenochtri believe they are in ascended Tydenborne watching the seas serving under Neptulon, the Niv'thded.