Ancient Lichen

Ancient Lichen is an herb that can be gathered by herbalists.

Source
Ancient Lichen nodes can be found only in instances, namely Slave Pens, Underbog, Mana Tombs, Auchenai Crypts, Sethekk Halls, Shadow Labyrinth, and The Steamvault. Rarely, it can also be gathered from dead fungal giants, treants and ancients. Requires 340 Herbalism to gather.

Ancient Lichen as an Ingredient
Ancient Lichen is used in the following recipes:

Alchemy

 * Elixir of Ironskin
 * Elixir of Major Defense
 * Elixir of Major Firepower
 * Elixir of Major Frost Power
 * Elixir of Major Mageblood
 * Elixir of Major Shadow Power
 * Flask of Fortification
 * Heroic Potion
 * Ironshield Potion