The Deadliest Paragraph
The Development section of K78 (CoS p. 84) describes an encounter with two Iron Golems, should the PCs attack them or the Warp Brazier kept here. Specifically it states:
... the doors of the room magically slam shut and lock ... On the first round, the golems fill the room with their poison breath ... Each creature in the room must make two savings throws.
A single Iron Golem has a Challenge Rating of 16. Their Poison Breath action does 45 damage on average on a failed save, meaning that you can expect the PCs to have taken 90 damage each before the battle even begins. And when it does, the Golems are immune or resistant to many of the PCs' potential attacks.
If the encounter is triggered:
- The doors in this room can be forced open (DC 25 Strength Check) or smashed (25 HP).
- Provided that the neither the Brazier (25 HP) nor the Hourglass (20 HP) have been destroyed, the PCs can warp out of this room using the mechanism described on Page 84.
Otherwise, your players will surely die here, the deadliest room in Barovia.