Horizon Zero Dawn Complete Edition launches on GOG on 24th November 2020 with full GOG Galaxy 2.0 features support.
Sony's once PlayStation 4 exclusive game launched on PC via Steam and the Epic Games Store in August. As you'd expect of a GOG release, Horizon Zero Dawn Complete Edition launched on the platform DRM-free. Horizon on Steam uses Valve's in-built DRM. There's no DRM on the Epic Games Store version.
Guerrilla's action adventure is the first first-party Sony game to launch on GOG as part of its recent push on PC. On the platform, Horizon is published by PlayStation Mobile, Inc., which is also the publisher of Helldivers, Guns Up!, Everybody's Gone to the Rapture, and Arrowhead Ultimate Co-Op Collection on Steam.