First off, there's a new version 6.66 patch with an update they say unlocks "the ultimate DOOM experience." This post has detailed patch notes as well as a full FAQ explaining everything that's changed. This makes all the game's multiplayer DLC free to all players, revises the progressions system, adds a new rune system to replace the hack module system, adds enhanced kill notifications, and resets all players' multiplayer level back to zero.
