The adventurers are cautious in approaching the devils, but are pleasantly surprised to find that they largely ignore the intrusion. The devils will say only that they have been given orders, which apparently do not involve fighting (yet). Moving along quickly before someone changes their mind, the party follows Ilda's directions to the divining pool. This is empty, and a dead cultist lies nearby. Investigation by Tom and Mella reveals that the cultist was killed by a ritual dagger, probably as part of an activation of the pool's power. They also find many arrows, some carved with images of a yuan-ti snake god - evidence of recent battle. Having been warned by Ilda of the pool's corruption, they do not attempt to use its power. Adjoining this chamber is a crypt, holding the tomb of Diderius himself. When they enter, the voice of the ancient wizard's spirit speaks! He has seen all that transpired here in his tomb - Varram activated the pool by sacrificing his own man, then was captured by the yuan-ti and taken prisoner into their stronghold. The spirit of the wizard knows how to activate a portal to lead them there. The adventurers would like some more protection before venturing forth, though, and ask Diderius if he knows of anything that may help in the battle against the snake people. He does know of some items of poison protection, though they will need to retrieve them from elsewhere in the tomb. With this guidance, the party returns, passing the devils again, and enter what used to be Diderius' chamber. They immediately spot several valuable objects, but before any can be retrieved, undead spirits materialize around them and attack! Brin is knocked unconscious and Noram is wounded, but the adventurers quickly regroup. Noram's holy symbol turns several of the spirits, causing them to flee, and the others handle the rest. A bit of healing magic brings the wounded back to their feet, and they find several useful items, including a set of magic goblets which can provide poison protection. They also find several books that match those which Ilda had asked them to return to the library. With their new items, the party starts to return to Diderius' crypt...but the devils attack! Their orders had been to attack anyone leaving that chamber. The adventurers quickly duck back inside and make a plan - with spells from Brin and Mella, they can turn invisible and escape the devils' ambush. Tiptoeing past the devils is a nerve-wracking process, but they succeed, and leave the devils watching an empty room. After this slight misadventure, the party chooses to rest near Diderius' crypt. Other than the talkative wizard telling stories of his past glories, nothing disturbs them. Refreshed, they ask Diderius to open the portal to the yuan-ti lair. The ancient spirit caused a door to open in the northern wall, leading into a dark tunnel. Lizardfolk guards looked up in surprise as the adventurers approached. Caught unaware, they grabbed for weapons, but Mella and Tom quickly spoke to them to forestall violence. Telling the guards of their purpose here, they asked to be taken to the yuan-ti masters. The lizardfolk were unsure what to do and sent one of their number to report, at which point the party decided that perhaps allowing the alert to be sent through the entire lair wasn't a great idea. They fell upon the guards and slew them to the last lizard. But this was not their only obstacle. Turning a corner revealed several more lizardfolk as well as some yuan-ti archers, guarding a narrow bridge over a snake-filled chasm. Swords, spells, and arrows flew from both sides in a brief but intense battle, and when the air cleared the adventurers were victorious over the lizardfolk and yuan-ti...but one had escaped! Knowing the alarm was raised, the party chose to proceed cautiously, making heavy use of Mella's owl familiar to scout ahead. They discovered several chambers, including a hatchery with many of the snake-like yuan-ti young and a chapel area with statues of the evil yuan-ti snake gods. These rooms they choose to pass by, and after a brief skirmish with more lizardfolk in a barracks room, find an empty jail area. Around the corner, the familiar spots a large chamber with many yuan-ti, including a large and powerful-looking priestess, and tied on an altar - the unconscious Varram! A frontal attack against such a strong force seemed foolhardy, so the adventurers came up with a devious plan. Combining their magical abilities, Mella and Brin generated an illusion of one of the yuan-ti gods. Sending the image ahead of him, Tom stood in the doorway, calling on all faithful yuan-ti to fall down and worship. Incredibly, the priestess did not see through this illusion and believed that her god had actually appeared! Quickly Tom demanded that one of the yuan-ti warriors retrieve Varram and bring him forward. Cowed, the warrior does so, and as soon as he approached the illusion, Tom struck him dead with an arrow! The yuan-ti saw this as the capricious cruelty of their evil god and cowered, hoping only to survive the whim of their god. Noram grabbed the dwarf and the party beat a hasty retreat before the illusion faded. Quickly returning through the lair, they reached the crypt of Diderius and asked the wizard to once again close the entryway. Retracing their steps through the tomb is an easy task, with the devils again avoided with invisibility. On the way, they stop to return the books to Ilda the ghost in the library, which allows her spirit to pass on from this realm to her final rest...a particularly pleasing outcome to Noram as a good cleric. A bit of healing returns Varram to enough health to be able to travel, and the party returns to their Harper contact in the Serpent Hills, who arranges transportation back to Waterdeep. On the way, they are able to question Varram. They learn that he no longer has the white dragon mask, and in fact had been hoping to find it using the divination pool in the tomb. But all his efforts told him only that the Cult has already reclaimed the mask, and then he was captured by the yuan-ti and severely beaten. Despite the failure to capture the white dragon mask, the Council is pleased with the capture of Varram, who can provide many details of Cult membership and plans. His information is old, but still useful. The dwarf is left in the custody of the Harpers, and the party rests for a few days before setting out on their next assignment.