Up to 5-20% Strength based on the charge time of your heavy attacks. Stacks 3 times.
12-24% Rending on Enemy Weak Spot Hit for 3.5s. Stacks 5 times.
4.25-5% Strength for every Enemy you Stagger. Stacks 5 times.
Ranged hits add 1-4 stacks of bleed to enemies.
Discover this but you can One-shot the assassination boss with the duelling sword.
You need the blessings: Thrust T4 and the perk: +25% Unyielding, + 10% weakspot damage.
Use fire barrel to regulate wounds.
Finish all bosses with the bolter, the build is not very effective on the others bosses like the Chaos spawn or the Plague ogryn.
(Very effective on the Beast of Nurgle and the assassination boss).
Take them by the back and aim for the head.
IMPORTANT: take a combat stimm it is obligatory: +15% or 20% damage.