Against the cult: the Forest Ruin (1.5)

Theran is confident in his orienteering: the workshop is below and to the east of the illusory pit trap containing the gold chandelier and all the medallions from the disintegrated Heralds. Whatever is beyond the door is about 20 feet below the overgrown veranda with the trapped statues.

Theran and Kragga both notice that the stains on the door seem to be fresh, and the wood seems to have swollen around the rusted iron bands and in the frame. In fact, Theran notices that the wood is "sweating" in places, beads of condensation visibly standing out on the darkest stains, toward the bottom of the door.

Theran feels the door; the lower half is wet as if with condensation. He also feels a tremor in the wood, as if something is scratching or rubbing against the door on the other side. The damp explains the mold, and the rust in this room and the previous one: there's much more moisture down here than in the ruin upstairs. The druid looks down at the bottom of the door, and sees that the wood, which was carefully fitted to fit neatly in the frame, has swollen down to connect with the floor. This would take a lot of liquid. There's no smell other than the mildew, so it's water or something similarly low odor. Toward the bottom of the door, the wood is slightly soft to the touch. The swelling would make it hard to open the door, but it would be easier than it looks to break it.