The Braystones

ANCIENT STRUCTURE / MONSTERS
If you're heading to the Braystones and enter the south caves below the Cave Portals, you can go north. Normally, it is one-way.
The first abbotess of the Far Abbey, Two-Eyed Tatoana, went to tear down the Braystones but never returned. Her body was never recovered.
The Mottlirischnayzin rebaptize The Braystones in slaves' blod whenever they've gotten more than 3 slaves on a raid.
The Thirty-One Spears want to tear down The Braystones but they're all spooked by the story of the first abbotess of the Far Abbey.
The Wuchdtilfin will, when they capture a grunzen, secretly crusify them at The Braystones to inflame human-grunz relations.