Styx: Master of Shadows follows the story of main character Styx, a goblin rogue who has drank magic sap called amber from an ancient tree located in a city inside of a mountain guarded by elves and humans. The sap granted Styx abilities but also caused him to lose memories proceeding his way to the tree the first time. Styx returns to the tree to drink more amber hoping it will restore his memories. Just as the rest of his race the goblins Styx is considered to be a pest and must be dealt with as pests. Styx must find his way through the city, and drink more amber for the chance to get his memories back.