Portal sicko beats the game with 'switched' wall textures so no surface is where it's meant to be, creating a whole new puzzling challenge in the process

Portal is not only one of the most mechanically inventive puzzle games ever made, but it's also one of the most elegantly crafted. Each of its Euclid-defying conundrums was built with surgical precision by Valve's mega-brain designers, created to slowly and specifically introduce you to the power of thinking with Portals...
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