In the previous session the Favorites of Selune vanquished the undead mage Vandomar, and recovered his journal for Berrian Velfarren. Now Berrian was able to give them some important information from that journal: The templars of Gardmore Abbey had brought a chaotic artifact from one of their crusades, and stored it in the Hall of Bahamut in the vaults. Berrian suspects that this artifact has something to do with the fall of the abbey, and asks the heroes to investigate. The vaults are one of two dungeons under Gardmore Abbey, accessible either via the barracks or the Hall of Glory. The vaults pre-date the abbey, having been a minotaur temple before the templars arrived. Since the fall of the abbey, minotaurs have moved back in, but so have gnolls. After constant fighting between the minotaurs and the gnolls, a mysterious leader arrived who was able to unite the two tribes.

When discussing what to do next, the group did not go for that obvious choice, the vaults. Instead they remembered that they had never finished the other dungeon under the abbey, the catacombs. They had cleared that dungeon, but had run away on facing the "end boss", a human who apparently was creating and controlling undead. Feeling more powerful (after a recent level up), the group decided to finish the catacombs first before tackling the vaults.

So the group made a plan of battle on how to enter the large room in which they had previously encountered that "necromancer". But on rushing in the surprise was that the place appeared to be empty. Another surprise was that the ranger who had opened the door got poisoned by a contact poison on the door handle, which hadn't been there on their first visit (which is why they didn't check for traps). So they all went into the room, which was full of sarcophagi. And after they had all moved, the sarcophagi closest to the doors, and thus right next to several of the characters, opened and released five vampire spawn undead. And from the other side of the room, the "necromancer" (who turned out to be an evil cleric), a vampire, and a basilisk rushed forward from hiding to attack the group.

The vampire spawn mobs were just minions, and quickly dispatched. Then the heroes made a probably wise decision to concentrate on the basilisk first. The wizard dazed the basilisk, and the warrior marked him, so the basilisk never got around to launch his area of effect poison attack, and died two rounds later. The vampire did some damage to the sorceress, but was the next to go down. The evil cleric was the toughest opponent, and caused the most problems, stunning several characters with an area attack. Although this wasn't their first "boss fight" in Gardmore Abbey, it was the first time where the group properly realized that the bosses in this place who had cards from the Deck of Many Things had some degree of control over those cards. The cleric had three cards, and used all three of them over the duration of the combat to good effect. But ultimately the Favorites of Selune prevailed, and got the three cards as well as a vampiric dagger from the vampire.

At that point I had expected them to discuss the cards from the Deck of Many Things, and how to control them. But instead they decided to go straight for the vaults. They chose to enter via the Halls of Glory, where they encountered the group of rival adventurers again, which they had already met three times (or rather seen signs of once, and actually met two times). As the previous encounter with the rivals had ended with the Favorites of Selune threatening the rivals to leave the abbey "or else", the group felt justified to now be true to their word and they attacked the rivals without further negotiation.

Now the rivals had obviously just been in a fight, and killed some spiders, so the group thought they would be in a good tactical position. But then they rolled somewhat low on initiative, except for the ranger, who did some serious ranged damage to the rival's wizardess. But the Favorites of Selune were all grouped together in the entryway, and to their surprise got attacked by the rival's drow rogue from behind. The drow had powers to make himself invisible, and thus was able to strike with great efficiency against the ranger and the wizard. Then the rival's "tank" warrior attacked from the front, making entry into the room difficult. And the rival's wizardess hit most of the heroes with a fireball.

At this point the sorceress came up with the idea to cast a dark cloud between the two groups, blocking line of sight. The cloud also damaged the rival's tank. The idea was to be able to concentrate on that tank and the drow, but the plan didn't work out like that. On being attacked the drow made himself invisible and teleported away, while the tank moved back through the cloud and into the room. So the Favorites of Selune found themselves with absolutely no target in sight, and in disagreement about what to do next. The sorceress was afraid that if she stopped maintaining that dark cloud, the group would be hit by a barrage of prepared attacks from their rivals. The wizard proposed to run away. But the cleric and the warrior had already used some of their strong daily powers to buff themselves for combat, and didn't want to completely reset the fight. With the Hall of Glory being partially ruined and missing its roof in parts, it seemed impossible to contain the rivals there while resting. So they needed to work out a plan on how to continue the fight from here. And as it was getting late, we decided to stop at that point.