The heavy smoke settled down, showing a real underground city, just like it looked hundreds of years ago. It was a giant human-made place under the earth, with many levels, tons of pipes crisscrossing everywhere, and buildings piled on top of each other.
A long time ago, a big monster messed up this underground place from the inside, making a huge gap in it. Now, this empty underground place can be seen again, and the big break in the ground lets the sun's bright morning rays shine in.
Down in the city, with all the loud sounds around, mutants felt scared. The ground was moving under them, and way up high, there was a narrow line of glowing light, showing a tiny piece of the sunny sky.
These underground creatures didn't have eyes. But they felt the sunlight coming into their usually dark place— it was so bright that it made everything clear and it made them feel weird. Their world was changing in big ways.