Portal 2
Chell and GLaDOS make it to the Enrichment Center near the surface and find Wheatley. GLaDOS attempts to short-circuit him by telling him a paradox. Unfortunately, Wheatley is not smart enough to understand it and the plan fails. Wheatley has discovered his new body gives him a feeling of euphoria when a subject solves a test. He tried to make cubes with legs to solve puzzles, but they were not good at it. Instead, he forces Chell to solve puzzles. As she solves more tests, Wheatley's feelings of euphoria become weaker, so he builds more and more complicated tests by smashing together test chambers that GLaDOS built.