I was approached by Zugg Zugg to complete a clearing. Apparently, they were not so successful with their choice of party composition in earlier multiple attempts. It does look like they made progress, but, they just couldn't finish it.
Further investigation showed an area of mushrooms that appeared to feast on meat instead of decomposition. Using Mage Hand, we were able to gather some coin from fallen wanderers of the past.
We discovered our fare in cages in the back of the dungeon. An ornate pentagram wasn't just drawn on the floor, it was carved into the ground with channels flowing to the middle. Being a servant of Dispater, I concluded the channels were for a flow of blood. Mazira had informed the party prior to entering that when she entered the caves, she involuntarily whispered "Give Me Blood".
I was able to do the math. Mazira's curiosity of the operation of the summons piqued and she requested that Mal's ape bleed into the circle. Mal was happy to oblige, which surprised me.
As expected, the blood summons worked and a Demon was summoned, who went invisible immediately and was able to manipulate shadow. Mal used his hellsights fast. I waited until I felt the Demon was hurting. It worked out without us talking about strategy. I was able to highlight shadows and the demon near the end.
This was a team fight and the team, surprisingly, did well without a lot of chatter. Even Mal was on point with his animal summons.
After escorting the prisoners home, dispatching the demon, we were confronted with a lava puzzle. Using Spider Climb, and ropes, we were able to get to an alcove protected by Lava where someone appeared to have blown himself up. I had to chuckle at his misfortune. Playing with powers you believe you can control can be fatal. While the others were looting the magics, I was able to obtain numerous volumes of very interesting topics.
When I get back, I must commiserate with Dispater about his desires for these tomes. There may be information contained in these that He finds useful.
Overall, we cleared the caves, returned the victims, dispatched a demon and I obtained numerous volumes that may be vital to Dispaters cause.