TGC writes: I know what you’re thinking. You know what I’m thinking. We may as well come out and say it right now. Portal. Portal, Portal, Portal. There. That’s that out of the way for the next few paragraphs. In case you didn’t know (and are therefore understandably perplexed by the preceding outburst), Quantum Conundrum is the latest headscratcher from Airtight Games, the studio responsible for 2010′s ambitious genre-buster Dark Void. The game is designed by Kim Swift, lead designer of Valve’s 2007 cross-platform smash hit Portal, and it shows.