Toughness

Toughness is one of the main attributes of a character. It is a high-level tanking stat that mitigates critical damage from NPCs.

Uncrittable
According to anecdotes on the forums for end game content the following toughness is required to reach uncritable status:


 * 50 - Tier 1 Expert Dungeons
 * 50 -  Expert Rifts
 * 100 - Tier 2 Expert Dungeons
 * 150 - Raid Rifts
 * 200 - Tier 1 20 man Raid content
 * 250 - Tier 2 20 man raid content

This stat reduces bonus critical damage, which is why 250 is the current cap - Tier 2 raid bosses hae a 500% damage bonus for their critical hits.