Limited Beta Test
Pre-order Demigod by Gas Powered Games and gain access to the exclusive limited beta program. This beta program is only open to those who pre-order the game directly through Stardock/Impulse.

From the main website.

In the past, they have only allowed new batches of testers during major updates.  (Beta 1, and then again when it was fully updated to Beta 2.)  Beta 3 should be coming up soon, so even if they aren't admitting new players this instant, they will likely let you in once Beta 3 comes out (hopefully this week).

But don't take my word as law.  That's just the pattern I've seen.  I have no idea what they are actually doing.

I pre-ordered the game 2 days ago and I am in the beta. It will say that the beta 1 is being downloaded, but he actually download the newest version. Updating was no problem either when a new version came out.

1. I preordered the game.  Will I get the beta?
   Anyone who has a preorder already (as of this writing) is 100% guaranteed a beta key.  That said, chances are still excellent that if you preorder the game at any point in the next few days, you'll probably get into the beta too.
    
2. I preordered the game.  Why don't I have a key?
   You will get the key when your preorder is charged.

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