FyrosfreddyGuild of Elias, yes. Except, Tryton doesn't have the resources for resurrecting people (it does require energy...), so homins still have to grudgingly pander to one of the higher powers for that privilege (resurrection is not a right), and try to do their Elias business in secrecy. (You're better of as a secret society if you're being hunted down by the higher powers.)
As I remember the lore, never fully developed in game to my disappointment, the Trytonists were hominists ... and thumbed their noses at the religions.
(Another good lore-founded reason to allow mixing up conflicting factions.)
Then again, Tryton cares only about homins. Extremist hominist, really. Doesn't care about Atys' ecosystem or anything.
It's a story of environmentalists vs industrialists (vs hominists), that now got replaced with goody-two-shoes vs the evil religions and bandits.