Hey,
i did the achievement with second try with a ranger soulbeast with a Iboga pet. So basically you stay merged with your pet to not share the aggro with your pet, kill some mobs far away from crystal with Aurene help, let Aurene to fight some away from veteran, use some shards to fill until you spawn the veteran, go get the aggro on the veteran quick, damage him (Condi damage works good) then go in the circle when he is low hp and unmerge with the pet and use fast F2 pet skill to pull the veteran in the circle, then kill him there quick. Be sure to use single target dps (I used daggers) because some mobs will always come to you...
You have 2 charges to fill the crystal after the veteran spawn and you want to kill the veteran inside the circle if you want to succed the achievement, if you need one more charge to fill the crystal completely, just kill a random mob inside there or just trow a shard. All you need to do is to kill the veteran inside the circle without filling the circle before he dies.. He needs to die inside. 3x crystals = 3x veterans, 1 per crystal needs to die inside.. The achievement is not very hard, you just need to play safe.
