Expansion for Neverwinter Nights
New 20-hour single-player campaign
Epic levels allow characters to advance as far as level 40
New prestige classes, feats, weapons, spells, and voice sets
2 new tilesets and additional content for the Neverwinter Nights Aurora Toolset
 
Neverwinter Nights: Hordes of the Underdark pits players in a battle to save the embattled city of Waterdeep from an ancient evil buried deep within the earth and stone of Undermountain. The game includes a new 20-hour single-player campaign, designed for high-level characters and set amid the famous city of Waterdeep and the foreboding Underdark from the D&D game's Forgotten Realms campaign setting. Hordes of the Underdark significantly expands upon the Neverwinter Nights universe, most notably with the addition of Epic Level gameplay. Epic Levels will be available for characters who have reached level 20, allowing them to advance as far as level 40.
In addition, Neverwinter Nights: Hordes of the Underdark introduces several new prestige classes, including the Shifter, a druidic class specialising in shape shifting; dozens of new feats, such as Epic Reputation, Craft Weapon and Armour Skin; a multitude of new weapons and spells, many designed solely for epic level characters; challenging new creatures pulled straight out of the Underdark, including Mind Flayers, Beholders and Driders; several new character voice sets for even greater character customisation.