The rarity of Ghastly Matriarch is Rare, and been equipped it takes a “Bundle” slot. At this moment the item is available for trade.
Ghastly Matriarch is a skin for Death Prophet. The skin was added to the game on October 22, 2014.
Ghastly Matriarch is currently one of the most popular skins, but it is rarely seen in the game due to its high price.