Portal 2 was released by Valve in 2011 as the sequel to Portal, set inside the decaying Aperture Science test facility run by automated systems and the AI GLaDOS. Its alarms and announcer warnings are part of that sterile, bureaucratic design, treating a nuclear core meltdown like a routine facility problem. Clips of the alarm spread through gaming videos, streams and edits, where players reused it outside the game as a danger alarm sound effect meme for overheating PCs, base attacks and other mock emergencies.