I don't know if it's a bug with the Del Kel DLC, but I've found a reliable way to farm purple and yellow items nearly indefinitely:
If you've recruited the Warsworn blacksmith, she will eventually ask you to help her clear some Niskaru from Flooded Cavern as part of the "Master of the Keep" quest line.
Go with her and finish the mission normally. The beach fight should consist of three Niskaru Hunters and one Niskaru Tyrant, although the mobs may vary depending on your character's level. Now, the Niskaru Tyrant drops some pretty good loot -- purples and yellows almost every time.
The Niskaru will respawn every three days or so (so just rest or putz around for a few days), allowing you to farm them indefinitely.
What I do (if I'm looking for a particular item) is save at the exit from Flooded Cavern, right before the beach fight. This way, I can kill them again and again until I get what I want.
Hope this helps!
Another way to go about it:
You can essentially do the same thing with the scavenger at Gravehal Keep. Send him on a mission, go back inside and rest for a day, then save before you exit the keep. Every time you load your save, exit the keep, and talk to him, he should have a different selection of items. If he gives you the "monsters chased me away," response, it doesn't matter how many times you load your save; you still have to run around and go grab the loot.
It seems that you can actually save your game right before talking to the scavenger at you keep after he's returned and each time you load, he'll present a different selection of gear. I recommend choosing to salvage the Alfar Warship every time, because it's the one that carries only weapons and armor. If "Alfar Warship" doesn't show up as an option during conversation, just back out and ask him again until it does.
Note that as you farm more purple and yellow gear, the loot pool for these items shrinks, as there are only so many unique items in the game. This means the chances of finding rare items through farming this way becomes less and less likely each time you nab something new.
It's tedious, and it scarily reminds me of farming WoW, but it's worth it in the end.
Upon further investigation, the Niskaru will respawn even if you take on other "Master of the Keep" missions. Don't know if it's a bug or not.
Anyway, between sending out my scout and slaying hundreds of the same Niskaru, I've been able to farm all of the top tier random-drop weapons and armor.
Let me know if this works for anyone else. The DLC seems a little glitchy, with chests and loot piles randomly respawning that contain the same crap they did the first time, as well as items getting stuck in inventory, whether I'm using the trainer or not.
Can anyone confirm that this farming method works for him/her?
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