Confront Gabrowg ( 172, -204, -517 ) Copy/waypoint 172, -204, -517 As soon as you get close, he'll send you flying - he has some kind of magic shield protecting him.
Find a way to defeat Gabrowg. Talk to Kutgurk at ( 145, -218, -434 ) Copy/waypoint 145, -218, -434 (the game doesn't prompt you to do this) and he'll give you two ideas .
"fresh hopper's feet" - Find a rabbit. There are a couple on the slopes north of Vrassath ( 579, -171, -412 ) Copy/waypoint 579, -171, -412. This is not a one kill, get loot. I had to kill 3 rabbits to get the rabbit foot. Right click it, select Attack, and loot Warslik rabbit foot from its corpse.
"spinn'-gem shards" - go to Luclinite Chunk ( 340, -245, -274 ) Copy/waypoint 340, -245, -274 (follow the river south from the bridge), kill a luclinite cluster, and loot luclinite shard from it.
Talk to Gabrowg and refuse to pay him. He'll attack. Kill him. He has a knockback, so get underneath his tent.
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(follow the river south from the bridge), kill a luclinite cluster, and loot luclinite shard from it.