Beware of Dragons on This Territory

Please note: Private property. Dragons, please keep your distance. A very ordinary sign. Allen struggles in the cramped space, trying to escape the darkness. Soldier: How is it moving? Allen: Is anyone out there? Allen kicks with all his might and sends the lid flying. Allen freezes, and so do the two soldiers. They stare awkwardly at each other, while on the ground lies a pitch-black coffin...