Doctor FIST

The third fight in the new Rank 9 tier of the Brawler's Guild, and one of the easiest for that tier.

The boss himself has about 13 million life, requiring about 109k sustained DPS to meet enrage.

As far as what he does, he does five main abilities:

Left Hook
Right Hook
Bodyblow
Uppercut
Hammer Fist

All these abilities will not one-shot you; they will hit you for around 100k damage if you're struck.

The first four are a cone effect in front of the boss. The last one, Hammer Fist, is a full 360 degrees within a 20 yard radius around the boss. All the abilities are clearly marked on the ground of the area they will affect with brownish dust, so it's easy to tell if you're in the zone of being hit. The best strategy I came up with as a 520 Hunter is to hug the boss and either run through him when he casts or side-step the Left Hook, Right Hook, Bodyblow, or Uppercut, and then Disengage out of Hammer Fist.

When I Disengaged out of Hammer Fist, I immediately ran back to the boss and hugged him, and repeated the process. Your mileage may vary depending on what class you are (I.E., Mages can Blink away).

That's really all there is to it. Good luck!

Proctologist extraordinaire.

Another good idea is to stun him during hammer fist. Each time he does it, he gains a 100% damage buff (permanent stacking). He resets his combo if you stun him during the hammer.