Nightmare Vine can be found throughout Shadowmoon Valley as well as Forge Camp: Wrath and Forge Camp: Terror in Blade's Edge Mountains and Throne of Kil'jaeden in Hellfire Peninsula. Prior to patch 2.4, it was only available in Shadowmoon Valley. It does not appear to grow any place in particular, it can be seen out in the open as well as tucked in between rocks.
As an ingredient
Gathering a Nightmare Vine has a chance to place a poison debuff on the gatherer called Nightmare Pollen that does 75 to 125 nature damage per second for 10 seconds.
- Patch 6.0.2 (2014-10-14): Stacks to 200, up from 20.
- Patch 3.0.2 (2008-10-14): (Undocumented) Nightmare Seeds will no longer drop when harvesting Nightmare Vine.
- Patch 2.1.0 (2007-05-22): The poison from picking this herb is now considered Nature damage instead of Physical damage, and has a reduced chance to poison the herbalist.
- Patch 2.0.1 (2006-12-05): Added.