Hail to the glorious (un) dead
The great Byssian Ocean
The great ocean of Byss is a strange case, as it lies behind the great waterfalls that come down from Elysia. It probably is the source of water for the great bog of Byss, as well, or at least whatever connexion it has with the Elemental plane of water must provide water for the bog, as well. Many scholars speculate that with its strange currents and odd defiance of gravity, the connexion must be at the top, supporting Elysia, and powering water down into the ocean and over the waterfalls, but none who have gone to explore and investigate have returned.
Regardless, the great ocean is a dangerous place. The merfolk found there are meaner and tougher than what outsiders report having seen, as the conflict with the merfolk seems to have been provoked by some foreign legion hunters who ventured near the ocean and thought the merfolk they found would be friendly and playful. They met a nasty end.
As well, there seem to be many Locathah, many more than what is reportedly usual, but since no one leaves Byss, it’s hard to determine what is fact and what is simple speculation, especially since many people are quite rattled when they arrive in Byss, as it’s not usually a gentle process.
Rumor exists that there were once more gentle folk in the ocean, but no one who’s spent much time in Byss really believes that. Apparently it even used to be warmer and lighter, with abundant life, but the deep-dwelling merfolk scoff at that, as the already think their coastal brethren have it pretty easy.
—Alix’s musings about Byss, reminiscences of training the foreign legion