The rarity of Cunning Corsair is Mythical, and been equipped it takes a “Bundle” slot. At this moment the item is available for trade.
Cunning Corsair is a skin for Riki. The skin was added to the game on May 17, 2017, it was created by katzeimsack.
Cunning Corsair has been recently added to the game, which makes it rather popular with the game community.