This is the most powerful weapon you can have for Act 5 Merc it beats Grief. Made him the strongest DPS merc of them all, don't need any auras guys :) :
Blinkie The Pvm Frenzy Barb [1.14] - Topic - d2jsp
Frenzy Barbarian Build Guide - D2R 2.5 Updated
Frenzy Barbarian Build Guide - D2R 2.5 Updated
D2 Frenzy Barb 2020 MAX dmg setup. Grief BA + Beast BA / Might / Conc. / Fana. - YouTube