In this developer walkthrough, GT “takes an in-depth look at the bonus single-player campaign Portal included in the Half-Life 2 Orange Box.” Continue reading to watch.

Witness the advanced techniques of Portal technology and how you can use these techniques to make yourself really sick

In this developer walkthrough, GT “takes an in-depth look at the bonus single-player campaign Portal included in the Half-Life 2 Orange Box.” Continue reading to watch.

Witness the advanced techniques of Portal technology and how you can use these techniques to make yourself really sick