I dismiss my dancing Lights and wait.

With a wave of your hand, the glowing orbs fade into nothing. 

Now the entire corridor is bathed entirely in sickly green torchlight. 

The regimented marching continues. Whatever is happening in the next room shows no signs of stopping, and its mechanical tone suggests that it could continue indefinitely. But at least you enjoyed a nice snack from your adventuring rations in the downtime!

What do you do?