• Six new areas including Neresis, the Hall of Mirrors, and the Machine God Temple
• New fighting style: wrestlers
• Dynamic experience economy
• Travel experience, much loved in version 1, returns in a new form
• Combat modes: turtle and aggro
• General combat maneuvers: desperate counter and wallop
• Major overhauls to six existing skill groups (up to you to figure out which ones)
• Faction improvements (see declare and desecrate)

For a historical retrospective, check out the changes introduced in the previous two versions.