Bethesda explained the details of how you'll be able to score your free copy of Fallout 3 after pre-ordering the Xbox One version of Fallout 4.

While Fallout 4 doesn't particularly have any console-exclusive in-game content, it does have a few features on the Xbox One that you won't be able to partake in while playing the PlayStation 4 version of the game. The PC version's mods will be available to download for the Xbox One version. Furthermore, pre-ordering the Xbox One version will score you a free copy of Fallout 3 for Xbox 360

Here's what Bethesda's official website had to say about this deal:

Before making your way to the wastelands surrounding Boston, give yourself a 101 primer on Fallout by returning to the Capital Wasteland in Fallout 3!

We’re excited to announce —  for a limited time – your pre-order of Fallout 4 for Xbox One will entitle you to receive Fallout 3 on Xbox 360. The code for Fallout 3 will be delivered to your Xbox message center in 7-10 days.  Redeem your code on or on your Xbox 360. Fallout 3 will have Xbox One backwards compatibility access when made available.

Bethesda's VP of PR and Marketing Pete Hines clarified things with Polygon about the two different ways you can get Fallout 3 for free:

  • Pre-order Fallout 4 as a download through the Xbox Store, and Microsoft will send you a code within 7-10 days to download the Xbox 360 version of Fallout 3. It will be playable immediately on that system and at an undetermined date when the game becomes backward compatible on Xbox One.
  • Pre-order Fallout 4 at retail, and you'll receive the Fallout 3 download code when you pick up your physical copy of Fallout 4 on its Nov. 10 release.

Unfortunately, retail pre-orders will have to wait until Fallout 4 launches to get their download code, but who would want to play the old game once the new one launches? Hines said this is to prevent people from putting money down, getting their code and cancelling their pre-order (which would get them Fallout 3 for free).

Fallout 4 will launch on Nov. 10 for PC, PlayStation 4 and Xbox One. We should note that this offer is only for the Xbox One version and is not available for the PC or PS4 versions of the game.