Ever since George Lucas decided to retcon the Star Wars continuity, prequels have been all the rage. Some attempts have been more successful than others: compare Star Trek: Enterprise and Hannibal Rising to, say, Smallville, and it quickly becomes apparent that prequels are a hit-or-miss affair. On the gaming side of things, The Legend of Zelda is the biggest culprit when it comes to endless retconning, but fans can hardly fault the series since they love it so much. With regressive storytelling being so risky, it’s no wonder companies like Valve opted to ditch prequels entirely and mainly resort to exploring backstory to flesh out their scenarios. It’s therefore been up to fans to take up the mantle of fully imagining a pre-GLaDOS Aperture Science facility in the aptly-named Portal: Prelude.