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Cubiculum Experimentorum - Chamber 22: Bumbleball, Cameras, and Screens

This introduces three new things I first used: bumbleball (an object that acts like a sphere, but jumps around when the player isn't looking at it), cameras, and screens from cameras.
The screenshot might make you think that the texture is Portal 1 style but its actually the Overgrown one from Portal 2. When I test my own levels, it generates a random screenshot and places it as a thumbnail.