Help, I can't defeat Admiral Irumion

[mreepi]

I am level 27 and I am doing the Punishing the Heretic quest. I can obtain the sacred water mask but I can't defeat Admiral Irumion. I have tried multiple times using 100% health potions. He is only 2 levels ahead of me, plus he is elite. He keeps wrecking me at his skill, spinning weapon. Am I doing anything wrong? I need help.

[Torchlight]

Strafe around counter clockwise at longer ranges or dodge between attacks and attack from behind.