GLaDOS in Lobby 7
|Date:||October 9, 2017|
The puzzling video game Portal was first released by Valve on October 9, 2007. In honor of its 10th anniversary, GLaDOS (Genetic Lifeform and Disk Operating System), the artificial antagonist of the game, made an appearance descending from Lobby 7.
Elsewhere throughout Main Group, posters resembling Portal's level signs appeared, with numbers matching the surrounding building's number.