Secret rooms

For sephiria secret rooms / hidden room searches.

Secret rooms are an achievement (“Traveler”) and a real loot swing.

Standard secret rooms

Special post-Erma room (community)

After defeating Erma, cross the bridge; on the left side of the table in the next room you can walk under the wall—no crack. Players report it as mostly lore.

Treat the crackless room as community experience; cracked-wall rooms are documented in the Steam Basic Guide with screenshots.

Sources