Now group7 is at the T intersection about 60 feet south of location7 in the corridor, no longer in sight of location7 which is around a curve in the passage so that it’s not directly ‘visible’ to Tremorsense.
Ror7 thinks “DITTOOOOOOOOOOOO!!!!!!!!” and the gum detonator thinks this over, decides it’s OOOOOOOOOOOOK, and a moment later the floor bucks. A staggering blast of sound and wind hits group7, immediately followed by the clatter of a stinging rain of stone shrapnel that splashes against the curving walls of the passage.
In the corridor, a brief, continuous crashing of rock tumbles from the ceiling onto the floor, with thud after thud nearly deafening to Tremorsense. The sound slows to a gravel spill, then stops. Fading echoes from the corridor suggest it is now a dead end, or mostly so.
A choking cloud of rock dust envelops the party, making it hard to draw a breath.
Immediately afterward, four more shockwaves arrive, rattling bones and teeth from more distant explosions, first from the east, and then from the north and west.
The uneven ceiling overhead in the corridor grinds and groans through shake after shake. Fine grit sifts down onto heads and shoulders.
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