Dungeons & Dragons Online is third main revision of the fantasy MMORPG based on the Dungeons & Dragons universe, following the initial release Dungeons & Dragons Online: Stormreach (2006) and the revised US version Dungeons & Dragons Online: Eberron Unlimited (2009). While for US players it has always been a progressive update of the same game (update 14 for the initial release of this version), this version introduces commercial expansions packs for the game, but retains the free-to-play model introduced in the 2009 version combining free players, premium players and subscribers.
The subtitle was dropped through the introduction of a campaign based on the Forgotten Realms in the Kingdom of Cormyr, next to the existing Eberron campaign in the continent of Xen'drik with the ability to mix characters and content of both campaigns. This update was launched alongside the first commercial expansion Dungeons & Dragons Online: Menace of the Underdark that introduces additional content such as new adventures and areas, the druid as a new class, and epic destinies with a new level enhancement system. This update also raises the level cap into epic levels up to 25. Some of the features introduced in the expansion are also available to subscribing players, even if they do not own the expansion.