Cloned Cube is a Portal mod. It takes place after GLaDOS' fall in Portal. You assume the role of Chell's secret clone. You have to escape or else you may just be tested to death. There is one obstacle. CUBiS is trying to kill you.
The second section of "training2" map in the Cloning Training Center. It is expected that you WILL be shot in this map.
Video: Youtu.be
Looks like Kleiner is pretty popular even in Aperture science.
That's not Kleiner...
He means the Popular Science magazine on the push board.