I'm looking for some advice regarding 2 traps that I'll be running tonight (traps and questions spoiled below):
Trigger proximity (alarm); Reset automatic
Effect The spell crucible summons three shadowfire elementals
(see Creatures, below). Then the crucible makes a targeted
dispel magic (CL 12th) against each non-elemental creature
in the chamber. As long as the spell crucible is active, any
creature casting a spell or using a spell-like ability in this
room is immediately subject to a counter spell (dispel magic,
CL 12th). If the crucible succeeds in dispelling an existing
spell or counterspelling a spell being cast, the affected
creature or caster is targeted by a fireball 1 round later (10-ft.
burst, Reflex DC 14 half). The fireball deals 1d6 points of fire
damage per level of the triggering creature’s dispelled spell
(or the combined level of all spells if the crucible dispelled
multiple spells on that creature).
The targeted dispel option for the spell dispel magic typically removes only 1 spell from the target if it's successful. The part at the end (bolded) of the trap seems to suggest that the trap might dispel multiple spells on each creature when it goes off.
Would you run it just like the spell, limiting it to removing only 1 spell? If you think the trap can remove more than 1 spell, would you roll once for each target, and dispel any or all spells on the target that that roll beats? Or, roll once against each spell on each target, dispelling or not dispelling each spell accordingly?
Trap: Opening the door into area K10 unleashes the firefall,
a waterfall of burning oil that pours down the grooves and
quickly burns any living thing below. The oil is contained in
large vessels underneath the flagstones of the landing at the
south end of the room, and is discharged through a number
of tiny pipes leading into the grooves.
If the PCs set off the trap, the oil pours through the pipes
and then ignites. The grooves swiftly disperse the flaming
oil through the room and down toward the door leading to
area K9.
FIREFALL TRAP CR 6
XP 2,400
Type magic; Perception DC 30; Disable Device DC 30
EFFECTS
Trigger proximity (alarm); Reset none
Effect The door to this room locks, and flaming oil fills the
trenches in the room—it affects the southern 15 feet in
round 1, affects the whole room in round 2, and flows under
the northern door to affect area K9 on round 3. This creates
flaming rain in the infinite pit in round 4; 4d6 fire damage
and target catches on fire (Core Rulebook 444), Reflex DC
17 half; heavy smoke, target is unable to act and spends
the round coughing and choking, Fortitude DC 15 negates.
A choking character takes 1d6 points of nonlethal damage
each round until it succeeds at a DC 15 Fortitude save. The oil
burns off after 5 rounds, but the heavy smoke persists for 10
minutes. When the smoke has dissipated, the doors unlock.
The paragraph text says it triggers when the door is opened, but in the trap's stat block, the 1st effect is, "The door to this room locks," and then other effects ensue. I can't quite tell what the intent is here. If the door locks (closing 1st?), then the PCs would be on the safe side, with the flaming oil getting to them (under the door) on the 3rd round — the 1st two rounds, the oil would be burning on the other side of the door. Maybe opening the door "arms" the trap, and then the trigger = "proximity" to the source (deeper in the room, where the oil starts), which would likely put some PCs in the area that's affected on the 1st or 2nd round.
Any suggestions? How would you run it?
