I'm running Dragon of Icespire Peak, and my players have encountered the Dragon Barrow.
This question relates to the mechanics of a specific part of the quest, so I've liberally used spoiler blocks to avoid spoiling this for any players of the campaign who might find this question.
If you're playing DoIP in any group (not just my players), don't read this question or the answers.
Section D5 is described as (emphasis mine):
This tunnel is only 2 feet wide. At the halfway point, a 5-foot-long pressure plate is hidden under a 2-inch-thick layer of earth. A character prodding ahead with a pole or similar tool can detect the plate with a successful DC 10 Wisdom (Perception) check. The first character to step on the plate causes the walls of the tunnel to collapse inward, burying all creatures in the tunnel. A buried creature is blinded and restrained, has total cover against attacks, and begins to suffocate when it runs out of breath (see "Suffocation" in the rulebook). Only a creature that is not trapped in the tunnel can clear away the collapse, using an action to open up the 5-foot-deep section of tunnel closest to it. A creature in that space is no longer buried.
Given that
the tunnel is 50', this means that the trap is 25' down the tunnel. The trap buries all creatures in the tunnel, so given it seems normal to assume that the PCs follow fairly close behind each other, this would mean all the PCs are caught, unless they explicitly say only one or two characters go down the tunnel and the rest stay in the room.
Because
Only a creature that is not trapped in the tunnel can clear away the collapse, therefore if the party are all in the tunnel (which seems likely), there will be a TPK because no-one is left to dig them out
Am I missing something, or is this likely to lead to a TPK, with no particular warning for the players?
Obviously as DM I can overrule and say that
the PCs left an unusually large gap between each other and so only some of the PCs are in the tunnel if/when it collapses
or say the last player jumps out of the tunnel (I could ask for a DEX save, but at that point they can't afford to fail it, so I'd probably rule they get free even on a 1, and just take damage)
but nothing in the module as written suggests this. I suspect I'm missing something?