Mostly used on zBarb with the Mob Rule rune in combination with Pride of Cassius.

Widely used defensive skill, provides 50% damage reduction and immunity to Crowd Control effects. Also very good on a zBarb with the Forced March rune. Mostly used with the Marathon rune for Torment or Bounty farming. Used from mobility, Fury gain and to trigger Earthquake s with Might of the Earth in combination with Lut Socks. Mainly used with Mortick's Brace to gain 50% increased damage and damage reduction. The cooldown can be reduced with Boon of Bul-Kathos, Obsidian Ring of the Zodiac or Messerschmidt Reaver. Widely used offensive skill, provides huge buffs with a longer cooldown. Very useful in solo as you don't have The Executioner or Frailty curse there that diminishes the effect. One of the few multiplicative passives the Barbarian has. With Frailty it's similar: TTK is 85s base So the DPS is 100/91.43 = 109.375%, that is 9.4% bonus DPS you get from Ruthless Let's say normally your TTK is 100s - and now we add Ruthless: TTK is always inversely proportional to your DPS so if you figure out the new TTK, it's easy to get DPS bonus from there. So the best way to calculate this bonus is by thinking in terms of Time To Kill (TTK). However, due to this very damage bonus you will spend less than 30% of the time fighting the last 30% of mob's HP.

Most people treat Ruthless as a 40% damage bonus that's active 30% of the time.

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