Master of the Molten Flow

I found on the Hunter's Wild Barrage, that just holding the Up-Arrow and either Left or Right arrow on your Keyboard causes you to dodge all the Spears, 100% of the time, so long as you're moving like this before the cast starts.

You'll look like an idiot to other people, for Keyboard turning, but at least you'll get the Meta with little effort.

They all do their special abilities in the first 5 seconds. If they don't - kill them.

Don't forget to loot them so they'll respawn faster.

Oh boy. This took a lot of time and caused me a lot of frustration.

The [npc=53085] part is easy. Just engage them in combat and wait until you get carried away by them, then kill them. I don't remember if I had to hit them with the [item=137663] or not, but I'd do it just be safe.

[npc=53143] is another easy one, as long as you have the [item=137663]. Kill the dog, then hit the Hunter with the Sword, and run away and wait. The Hunter will be stunned for a couple seconds due to the sword. If he doesn't cast [spell=98369] within 5 casts, kill him and try again. According to another comment, the yellow or yellow/red ones seem to have it more often. Once he does cast it, all you have to do, as noted in other comments here, is run in circles until the cast finishes (Hold Forward+Left or Right) and you should get it once the cast finishes.

The [npc=53093] part is what took me the longest. With 2 squishes under WoW's belt, it took some time. What I did was I rounded a couple of them up, hit all of them with [item=137663] and stood there as they continuously cast [spell=98210] on me. Their health won't go down, but eventually, given enough time, they will die.

Hope this helps, and happy hunting!