2K Games announced today that Minerva's Den, the next single-player expansion of BioShock 2 will be released on the Marketplace on August 31 and will be downloadable for 800 Microsoft Points. The content will add three new scenarios and we will play as a new character by offering a parallel plot that dell'orginale campaign. Furthermore, the publisher informs us that those who have already purchased the previous contents titled "Evidence Protector" will receive a bonus item, the Master Protector Tonic useful to enhance the skills of Little Sister.