High Quality Content by WIKIPEDIA articles! Neverwinter Nights 2: Mask of the Betrayer (also referred to as NWN2:MotB or MotB) is a computer role-playing game developed by Obsidian Entertainment and published by Atari. It is an expansion pack for Neverwinter Nights 2. It was released in Autumn 2007 for the PC in North America, Europe, and Australia. Like the first game, Mask of the Betrayer is set in the Forgotten Realms campaign setting of the paper and pencil roleplaying game Dungeons Dragons and employs the 3.5 edition rules.