It's going to get you... it's just a matter of time. The undead are after you, and the only way to delay your inevitable demise is to run down the Hell Hall!
Run down the hallway avoiding the obstacles. Hit an obstacle and you'll fall back. Fall three times and it'll get you.
A context menu should be shown when right-clicking or, on touch devices, long-pressing in the game. This menu especially allows to play in full screen and control the volume.