The rarity of Eldritch Gnarl is Mythical, and been equipped it takes a “Bundle” slot. At this moment the item is available for trade.
Eldritch Gnarl is a skin for Treant Protector. The skin was added to the game on September 14, 2016, it was created by leshiy.
Eldritch Gnarl has been recently added to the game, which makes it rather popular with the game community.