What is Gamma Energy?

Gamma Energy is a free mod for Portal with a brand new story and over 30 test chambers.

What do I need to run Gamma Energy?

You'll need to own Portal and a computer capable of running it. if your computer is under four years old, you're probably OK.

Will Gamma Energy run without Portal?


Will Gamma Energy run on my pirated copy of Portal?

No, and I have no sympathy for you.

How much does it cost?


How difficult will the game be?

It's a little bit harder than Portal, but a whole lot easier than Portal: Prelude. There are also a few Advanced Chambers that could prove quite difficult, for those who seek a challenge