The Guardian Brotherhood had four of the five coins of Baphomet, and had just finished fighting the psychic sentinel and decided to attempt to take a rest for the first time in the labyrinth. When they woke the next day, they were safe, and continued on their way.
They had a more difficult time navigating the corridors this time, however, and found themselves in two different encounters before making their way to the next chamber.
The first was with the will-o’-wisp from earlier, only it had help this time, in the form of two astral stalkers. While the stalkers acted in tandem, trying to flank and out maneuver the Guardian Brotherhood in the narrow corridors of the maze, the will-o’-wisp instead focused on blinding the heroes.
It was more difficult than expected, and featured another rambling appearance by the rust monster, but the heroes eventually made it past the ambushers and headed back into the maze, where they promptly got lost again.
This time they were attacked by a fire elemental, which dropped from the ceiling to attack them. This encounter was much easier, and the heroes escaped mostly unharmed.
Finally, after wandering for several hours, they came upon a small archway with stairs leading down to a pool room. There were fire pits in the four corners of the room, and suspended above a platform at the center of the pool was a living fireball spell. When they entered the room nothing seemed to happen, so they began searching to see if they could find another coin.
When Sid dipped his toe into the pool, predictably, they were attacked by the room’s guardians – four astral giants and the gargantuan living fireball. While the fireball rolled around the room trying to immolate the heroes, the giants teleported and tried to knock them unconcious with their tree-sized quarterstaves. It was a tough fight, but with each giant that went down, the room got easier and easier, and eventually the heroes won in the end.
After completing the battle, they again searched the room, and found a way to lower the water level, which revealed a teleport circle, presumably to the next room in the maze.