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.
+4.5-6% Close Range damage on Repeated Hit. Stacks 5 times.
+1-4 Burn Stack(s) on Critical Hit to a maximum of 3-12 Stack(s).
https://www.youtube.com/watch?v=3AbK05gyC4Q