Forza Horizon 1 and it’s DLC is to be de-listed from the Xbox Store on October 20. You will still be able to purchase the disk, but the digital version will no longer be for sale.
Those of you lucky to pick it up when it was in Games with Gold will still have access to the digital version, but if you haven’t got the game, then the digital version won’t be purchasable after October 20.
The de listing was confirmed on the Forza Motorsport website.
While we’re reveling in the euphoria of launching a brand-new Forza game, I do have an important update regarding the original Forza Horizon. On October 20, the original Forza Horizon for Xbox 360 will reach “End of Life” status.
That means that the game and its associated DLC will no longer be available for purchase. Players who own Forza Horizon before that date will still be able to download and play the game and its associated content as normal. After that date, however, Forza Horizon and its associated DLC will no longer be for sale.
Source: Forza Motorsport