Visual so we're on the same page:
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The yellow squares are what you know and can see. The 'G' marks where the bound and unconscious guard is. Most of the PCs are in the hallway, and Bala is moving toward the right away from where most of the fighting noises is coming.

The left side is the direction from where you heard the loud conversation. The right side is where you heard the explosion. The lightly dotted squares have light rubble (affects things like tumbling and general movement). The medium dotted squares have a bit more rubble. I'll post specific movement rules for that if necessary.


Bala goes right down the hallway. Peeking around the corner she sees:
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Lots of rocky rubble, some of which are lightly on fire. There are three burned bodies among the debris. Along the outside wall, there is a 15' wide hole into what appears to be another cell; it's about 15' down the hallway. The inside wall across from the hole is severely dented, but still whole. Also, the corridor here is narrower -- only 10' wide -- and it extends for about 100'. You don't see or hear any active fighting down this way.