DOOM's Free Update 4 is available now and brings a bunch of exciting new additions to the game, including Arcade Mode, new multiplayer modes, and classic DOOM modules in SnapMap! Here's a list of what's new:

Single Player
Arcade Mode
Return to the critically-acclaimed single player campaign in this new game mode that has you competing against your friends and players from around the world for the highest scores. Fight like hell against demon hordes, with a fully unlocked arsenal of guns, Praetor suit upgrades, and runes. Earn medals and achievements, play on every difficulty, and challenge yourself with the new scoring system that rewards aggression and accuracy.
Various fixes and performance tweaks
Multiplayer
2 New Modes
SnapMap