This is a video of a video game. The game appears to be set in a dark, dungeon-like environment with stone walls and floors. The main character is a knight wearing armor and holding a sword. The knight is walking through the dungeon, and at one point, he encounters a demon. The demon is black with glowing red eyes and appears to be attacking the knight. The knight fights the demon using his sword, and after a brief battle, the demon is defeated. The knight then continues to walk through the dungeon.