Avernum 2: Crystal Souls is a single-player role-playing video game developed by Spiderweb Software. It is the second game in the Avernum trilogy. The game was released for OS X and Microsoft Windows in January 2015, The iPad version was released on the App Store on April 15, 2015. Avernum 2 was released simultaneously on Steam, GOG.com, and the web site of Spiderweb Software.