Murky Delve

Murky Delve, also known as Cave of Tribulations, is a location in Toussaint and where a hidden chapel to the Prophet Lebioda is located.

For those on a pilgrimage, this cave tested one's character, whether it was pleasure, greed, or helping out those in need. While there was no wrong way to do things, those who showed restraint, were generous, and helped others, tended to fair better than those who weren't.

On first entering the cave, Geralt can come across a purple mist that soon has him hallucinating the trials, including nude women, beggars, and a person being attacked by kikimore workers and, finally, the prophet himself, after which the hallucination ends and the purple mist disappears.

Trivia

 * the hallucinogenic purple mist is a possible reference to Fallout's Vault 106, where the player is overcome by a purple tint and they start to hallucinate people that aren't there.