Part of the September challenge.
Tombs of the Naruth
Room Six: Path of the Faithful
Accessed via the second door in room three.
This long room is where the faithful passed through to their ultimate transformation.
A long, wide room with plain walls and a dusty dry floor of cross-shaped flagstones; at the end is a stone door with a pattern of a sunburst, painted in gold, before it.
The opposite door is locked, with no obvious way of unlocking it. The pattern is gold leaf, flaking but intact.
Before the rear door is a sunburst pattern engraved into the floor, each line painted with flaking gold leaf (100 gp worth); the pattern radiates magic and blocks access to the door.
When anyone steps inside the sunburst, a powerful white light illuminates them, and unless their eyes are tightly shut (or otherwise protected) they must make a save versus magic or be struck permanently blind; success means they are merely blinded for 1d6 turns.
The door then unlocks, and remains so for a round before locking again.