In order to activate this game, you will require a third-party 'Steam' account. For full details on how to activate please follow this link: https://support.steampowered.com/kb_article.php?ref=5414-TFBN-1352
Assetto Corsa: Ultimate Edition is the most complete version of the universally acclaimed driving simulator, offering all the DLC & updates ever released for the game (Dream Pack 1-2-3, Tripl3Pack, Porsche Pack 1-2-3, Red Pack, Ready To Race, Japanese Pack and Ferrari 70th Anniversary DLCs).
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Assetto Corsa Ultimate Edition