Tap! Tap!
The cavern's rocky ceiling cracked. A tiny pebble fell down and landed on the stone ground. The cavern was filled with the rhythmic sound of tapping. When the rocks landed on the ground, the sound reappeared, and it kept repeating.
From the narrow crevices, a shimmer of light appeared.
Crack!
The yellow crystals hanging from the ceiling cracked. A yellowish light escaped from the cracks in the crystals. The light was released into the cavern. Then, the light faded away, and the yellow crystal dimmed down.
Soon, the yellow crystal was yellow no more. The crystal's interior became brown and musky.
The only light source was coming from the crevices. They became bigger and released more light into the cavern. Soon, the light was bright enough to envelop the whole rocky environment.