A few months ago, Sony confirmed its PS4 exclusive Horizon Zero Dawn would mosey over to PCs this summer, and there is a placeholder on Steam for when that happens (or for whenever preorders open up). No pricing has been announced, though you can score the game for free if you purchase one of six eligible Ryzen 3000 series desktop CPUs.
As spotted by a member of Resetera's forums, it is part of a new "Fight back with AMD Ryzen" promotion AMD is running for a limited time. Eligible processors include the Ryzen 5 3600 and 3600X, Ryzen 7 3700X and 3800X, and Ryzen 9 3900X and 3950X. Many of which get the thumbs-up from us as some of the best CPUs for gaming.
This is an "EMEA ONLY" promotion, as AMD states in all-caps on its terms and conditions page. It's not clear if AMD plans on expanding availability at some point.
In the meantime, there are several participating retailers, including Scan, OverclockersUK, and Chillblast. Once you purchase an eligible processor, you should receive a coupon code, which you can redeem at AMD's game redemption portal. The offer is good on purchases made by the end of June 30, with coupon codes having to be redeemed by July 30, 2020.