Portal began as Narbacular Drop, a freeware student project from the DigiPen Institute of Technology that a Valve developer spotted at a career fair; after a pitch to Gabe Newell, the whole team was hired on the spot. This episode explains how fewer than ten people with almost no art budget recycled Half-Life 2 assets, why that decision tied the game to Aperture Science and irritated Half-Life's writer, and how playtesters getting stuck on decorative pipes led to the sterile, clinical look inspired by the film The Island.

We break down momentum conservation, or speedy thing goes in, speedy thing comes out, the flinging maneuver, and the instructional scaffolding that teaches non-Euclidean thinking without a single tutorial box. Writers Erik Wolpaw and Chet Faliszek created GLaDOS to solve a motivation problem, and we trace her slide from po ...