Items, NPCs, quests, objects and spells of patch 1.12.1, read live from the realm itself.

Thorny Vine

NPC	Level	Zone	Chance
Fel Lash Elite	56	Dire Maul	22.2%
Death Lash Elite	57 - 58	Dire Maul	21.8%
Phase Lasher Elite	54 - 55	Dire Maul	20.4%
Whip Lasher	54	Dire Maul	6.64%