DC Universe Online DCUO is a free to play action combat massive multiplayer online game.Set in the fictional universe of DC Comics. Developed by Daybreak Game Company and co published by Daybreak Game Company and WB Games the game was released on January 11 2011.DC Universe Online DCUO is a free to play action combat massive multiplayer online game.Set in the fictional universe of DC Comics. Developed by Daybreak Game Company and co published by Daybreak Game Company and WB Games the game was released on January 11 2011.