And you will not be locked into the Show Me Mastery difficulty should you want to drop it down for your next run. The PlayStation blog detailed that you can swap between these difficulties in between attempts. God of War Ragnarok: Valhalla has 5 difficulty settings, with the hardest being Show Me Mastery.
Each room you complete will earn you rewards like Runic Attacks for your weapons and other enhancements, as well as currencies that may or may not disappear when your current attempt is over. Valhalla blends a slowly expanding story of Kratos' personal journey into both his past and future, while also having you fight through a series of randomized encounters that become increasingly difficult. You will however have access to all weapons and a fully upgraded skill tree at all times. As it is a separate mode from the main story, when you begin God of War Ragnarok: Valhalla you will not have any armor and equipment and need to earn equipment by playing Valhalla.
