The rarity of Fathomless Ravager is Rare, and been equipped it takes a “Bundle” slot. At this moment the item is available for trade.
Fathomless Ravager is a skin for Shadow Fiend. The skin was added to the game on May 17, 2017, it was created by Attasik.
Fathomless Ravager is currently a rather popular skin, which is often seen in the game.