Steam's Achievement Sets beta aims to stop new content breaking your completion status

Valve is testing a new Steam feature called Achievement Sets, allowing game developers to group achievements into collections. This aims to prevent new content from disrupting players' progress and make it easier to see what they've completed. Developers can create sets with specific goals, such as separating single-player and multiplayer achievements.

Completing a set earns a trophy on the player's profile. DLC achievements are grouped separately and only become visible when the player has access to the additional content. Players can also archive sets or individual achievements. An updated achievements page lets players compare progress with up to three friends, including rare achievements and completed sets. The feature is currently in beta and will continue to evolve with developer feedback.