Portal 2
While Chell solves the puzzles and GLaDOS repairs the building, Wheatley works behind the scenes to free Chell. Once he does, they try to sabotage GLaDOS's weapons, including her turrets and neurotoxin. In a confrontation with GLaDOS, Chell presses a button that removes GLaDOS from controlling the laboratory and puts Wheatley in her place. In anger, GLaDOS reveals that Wheatley is an intelligence-dampening sphere, created by scientists to distract GLaDOS from evil by distracting her with a constant stream of stupid ideas. Wheatley is outraged and becomes power-mad. He puts GLaDOS's AI into a potato and turns on Chell, sending them both deep underground to an abandoned part of the facility.