The rarity of Forlorn Descent is Mythical, and been equipped it takes a “Bundle” slot. At this moment the item is available for trade.
Forlorn Descent is a skin for Undying. The skin was added to the game on May 16, 2018, it was created by DNADota.
Forlorn Descent is currently one of the most popular skins, but it is rarely seen in the game due to its high price.