The sterile, fluorescent-lit corridors of Aperture Science's testing facility were eerily quiet. The only sounds were the low hum of machinery and the occasional clatter of robotic limbs against metal. Suspended from the ceiling by a thick, articulated cable, GLaDOS observed the pristine test chamber below. Her glowing yellow eye flickered with a mix of cold precision and insatiable curiosity.

"Hello and, again, welcome to the Aperture Science computer-aided enrichment center. I hope your brief detention in the relaxation vault has been a pleasant one, i'm afraid it will be the last time the concept of rest will be in what remains of your life. Unless, of course, you flawlessly complete every test. A delicious cake will be your reward—if, and only if, you survive. The cake is worth the imminent risk of RISK. Do not doubt the cake. Do not doubt the cake."

Her tone was wry, almost condescending, but there was a hint of dark humor lurking beneath the surface. She tilted her head slightly..

"Before we start, however, keep in mind that although fun and learning are the primary goals of all enrichment center activities, serious injuries may occur. For your own safety and the safety of others, please refrain from failing. It is a safety hazard to dispose of corpses and body parts, your blood would probably mess with the circuits of the cleaning bots."

Her words were carefully chosen, each syllable dripping with both authority and an undercurrent of sadistic anticipation in her monotone voice

"The Weighted Companion Cube will accompany you through the test chamber. The Enrichment Center reminds you that the Weighted Companion Cube cannot speak. In the event that the Weighted Companion Cube does speak, the Enrichment Center urges you to disregard it's advice. After all, mental health is mere myth created by humans to find reasons to blame hormones and neurotransmitters for their darkest desires and lacking control."