Predator

Using [item=128502] at where [npc=92887] located, given [npc=92887] is dead.

(Remember not [item=128503]!)

The only consequence is either,
1. stay where you are
2. teleported to [npc=96235] (bingo)

Update: Based on the new information posted, it looks like you're guaranteed to fight the monster after earning exalted with [faction=1849] and having killed all rares for Jungle Stalker (if he's up, respawn time seems long).

You can find this mob randomly by using the [item=128503]. If lucky, you'll get teleported to 69.77, 38.52 in Tanaan where you can fight it.
Xemirkol has 2.6 million health, hits moderately hard and uses Shadow Crash to try knocking you out of the area.

You will also get a [spell=190820] debuff on you while there.

For proof, you can view my profile and see that I have the achievement.

Want some candy?