Neverwinter Nights 2: Mysteries of Westgate

Neverwinter Nights 2: Mysteries of Westgate (NWN2:MoW) is an expansion pack for the role-playing video game Neverwinter Nights 2. It was developed by Ossian Studios and published by Atari on April 29, 2009. The player creates a character and controls it, along with a group of three pre-designed companions, journeying through the game world. The gameplay is very similar to that of the base game. Mysteries of Westgate also includes new monsters, music, and other tools, which can be used by players to create their own Neverwinter Nights 2 levels.

The game takes place in the Forgotten Realms world, a Dungeons & Dragons campaign setting, in the area of Westgate. The player creates a character at the start of the game who finds a cursed mask belonging to the "Night Masks", a thieves' guild at war with two other organizations. The player chooses which of these other organizations to side with, and embarks on a quest to lift the mask's curse.

Mysteries of Westgate was made after Ossian Studios' successful work on the 2006 expansion pack Darkness over Daggerford. The game's release was delayed to April 2009, despite its completion in September 2007, because of digital rights management issues and coordination difficulties between the three companies involved. Mysteries of Westgate met with mixed reviews; the game's plot and small amount of spoken dialogue were criticized by reviewers, while its music and low price for overall content were praised.