A barbarian can resist incoming attacks, shrugging off 3% of all damage. This increases by 1% at 5th level and every three barbarian levels thereafter, for a total of 9% at level 20.
Notes
This reduction was introduced in Update 39 Patch 2 Release Notes, replacing classic Damage Reduction feature of PnP Barbarians.
It is a straight percentage of damage reduced before Physical and Magical Resistance Rating calculations.
Some core enhancements in the Barbarian Occult Slayer line increase this by 1%, for a total of 4% available from the tree.