Disco mode

Disco mode is an easter egg in which lighting in the Atrium will begin to switch to random colors alongside disco music that players throughout the area. The music plays for about 5 ½ minutes before the lighting effects are reset and the music finishes.

Activating the effect
To start the disco mode easter egg, two buttons in completely different locations of the facility must be pressed in succession within 10 seconds of each other. The first button is present near the wall on the southern side of the Headcrab parasitology lab. After pressing this button, a secondary button will appear on the wall in the Atrium, beeping steadily to indicate it should be pressed. After the second button is pressed, it will be hidden and the event will trigger.