This time I present you with a very simple ranger solo (with henchies) build to farm the kurzick's faction quest: The duel of the houses.
The build:
Spike trap {Elite}.
Dust Trap.
Barbed Trap.
Flame trap.
Frozen Soil.
Serpent's Quickness.
Storm Chaser.
Dodge
Edits: I'll be upgrading this build to make it more effective.
Removed Whirling Defense since it'd cause the Duelists AI to run away from the traps. Added Dodge instead to make it quicker to the Duelists spot
Wilderness Survival (12+3)
Expertise (12 + 1 + 1)
Steps:
1. Travel to Brauer Academy.
2. Pick 7 henchies (I use myself both monks, ritualist, both tanks, vile and domination henchies).
3. Run out the north exit.
4. Talk to the Duel Master Vaughn next to the ressurection shrine to get the quest.
5. Follow the quest arrow quickly by using storm chaser, arriving to the Duelists before the Master Duelist will give you enough time to set your traps before they turn against you.
6. Stand in between the duelists and lay down all of your traps making sure you activated your Serpent's Quickness.
7. After laying two sets of traps, run outside of the aggro buble of the duelists and set a frozen soil.
8. Go back into the mob again and start setting traps until the Duelists turn against you.
10. Once they turn against you, watch them explode
11. Redeem your quest reward and repeat the process.
This is a very easily farmable quest that earns you 400 kurzick faction, 2,000 experience and 150 gold pieces. There is casually a chest that you can open right on top of the Duelists spawn so be prepared with some keys. Hope you enjoy this mini guide :P

thats how i originally completed the quest the first time as my mesmer