E3 2016 - Doom's First DLC - Unto the Evil coming next month!
The first premium DLC for DOOM is coming next month, titled Unto the Evil it which includes three new multiplayer maps (Offering, Cataclysm, and Ritual ), new equipment, a new weapon, and the Harvester--and a new player-controlled demon called The Harvester.
DOOM: 2016 #BE3 Showcase Presentation
In addition to that it's also been revealed more free content is coming to DOOM, Snapmap will be receiving some Hell theme tools as well as further improvements to creating single played themed experiences in multiplayer. We're also getting more multiplayer modes such as three free-for-all modes, as well as classic death match, too.
Source: http://uk.ign.com/articles/2016/06/13/e3-2016-dooms-first-dlc-is-unto-the-evil