NightCrawler

"You are an explorer of abandoned places, one night you made your way into an underground laboratory, it was abandoned, when you entered the entrance from behind was rarely covered with earth and stones, you were locked, but you continued on your way, the strange thing is that there was still light in this laboratory, as if someone still lived here. "
Suddenly, you hear a sound coming from the door. It sounds like someone is there, but it doesn't seem like it's human. You stop, and the sounds coming from there stop as well. It seems like the beast there heard you. You hear footsteps approaching the door, and they're massive.