Steam has started beta testing achievement sets, a new system that will allow grouping trophies by categories, separately accounting for add-ons, and not resetting progress after new content is released.
Developers will be able to combine achievements into sets as they see fit: for example, separating single-player and multiplayer challenges or creating separate categories for character classes. Each set will have its own progress bar and trophy in the profile.
Sets for the main game and add-ons are provided. Achievements from DLC will not be counted in the statistics of those who do not own the corresponding content. Developers will also be able to archive seasonal and temporary achievements: they will remain with those who earned them and will not affect the progress of other players.
The updated achievements page will allow filtering challenges, comparing results with three friends, and tracking completed sets. The "Perfect Games" section will be renamed to "Completed," and the perfectionist showcase will start taking into account games with fully closed sets.
The beta version is available to players and developers. Among the first supported games are Portal 2, Left 4 Dead 2, Euro Truck Simulator 2, Forza Horizon 5, and Crusader Kings III. More details can be found here.