Part of the Orange Box, this 2004 game is a very fun brain teaser mind challenging game. It seems to just be a puzzle game at first, but continue on and you might find more than a few holes in the wall.

Portal walkthrough part 10 with commentary! I hope you can hear it, this is sort of my test run videos of using my mic on Vista, so I'll get it fixed when I do Half Life 2.

Gameplay by Mario11168.