The rarity of Arachnarok is Uncommon, and been equipped it takes a “Bundle” slot. At this moment the item is available for trade.
Arachnarok is a skin for Broodmother. The skin was added to the game on August 31, 2016, it was created by Anuxi.
Arachnarok is currently one of the most popular skins, but it is rarely seen in the game due to its high price.